Vision for European Astronomy and Astrophysics at the Antarctic Station Concordia, Dome C in the Next Decade 2010-2020

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C In the next decade 2010-2020

Prepared by the antarctic research, a european network ARENA for astrophysics consortium in fulfilment of the work programme of the EC-FP6 contract RICA 026150 Silent with star-dust, yonder it lies - What pilgrims travel the Winter Street? The Winter Street, so fair and so white; Are they not those whom here we miss Winding along through the boundless skies, In the ways and the days that are vacant below? Down heavenly vale, up heavenly height. As the dust of that Street their footfalls kiss Faintly it gleams, like a summer road Does it not brighter and brighter grow? When the light in the west is sinking low, Steps of the children there may stray Silent with star-dust! By whose abode Where the broad day shines to dark earth sleeps, Does the Winter Street in its windings go? And there at peace in the light they play, And who are they, all unheard and unseen - While some one below still wakes and weeps. O, who are they, whose blessed feet Pass over that highway smooth and sheen? Miss Edith Matilda Thomas (1854-1925)

Table of contents Table

2 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Table of contents

executive summary 6

1 approach and scope 12 1a Context 15 1b Brief historical overview 15 • Windows into geospace 16 • First steps of photonic astronomy in Antarctica 16 • Super seeing conditions on the Antarctic plateau 17 • Towards an observatory at Dome C 19 1c How ARENA worked

2 arena deliverables 24

3 site quality assessment 28 3a Available data 29 • Precipitable water vapour (PWV) 29 • Sky brightness at infrared wavelengths 30 • Optical sky brightness, fraction of clear nights, and visual extinction 30 • Temperature and wind profiles 30 • Seeing e0 30 • Outer scale L0 2 30 • Boundary layer and Cn(h) profiles 31 • Coherence time t0 and isoplanatic angle q0 31 • Additional note concerning day-time observation conditions 32 3b What is needed to finalize the site characterization at Dome C

4 astrophysics at dome c 34 36 4a Wide-field optical and infrared astronomy 36 • Working group activities 36 • Science and context 37 • Dome C potential 37 • Science cases 39 • Instrumental requirements 40 • Roadmap and funding 42 4b Submillimetre-wave astronomy 42 • Working group activities 42 • Submillimetre astronomy: science and context 43 • Dome C potential and atmosphere transmission 44 • Science cases for submillimetre/far-infrared astronomy at Dome C 44 • Telescope requirements 45 • Roadmap and funding 46 4c Optical and infrared interferometry 46 • Working group activities 46 • Science and context 47 • Dome C potential

3 .A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020)

47 • Instrumental requirements 49 • Conclusion and roadmap 50 4d Long time-series photometric observations 50 • Working group activity 50 • Science and context 50 • Potential of Dome C 51 • Science cases 53 • Instrumental projects for time-series observations 54 • Roadmap and funding 56 4e CMB experiments 56 • Precision CMB measurements: the unique potential of Dome C 58 • Proposed projects 60 • Feasibility 62 4f Solar astrophysics 62 • Working group goals, activities and organization 62 • Solar astrophysics in the space and ground context 63 • Dome C unique assets for solar observations 64 • Solar science cases 65 • Proposed facilities and infrastructure 66 • Logistic footprint on the Concordia station 66 • Conclusions 5 logistics and polar constraints 68 5a Astronomy at Dome C and logistics 70 5b Plan for the installation of a large instrument

6 public outreach 72 6a Introduction 73 6b ARENA leaflet 74 6c ARENA public outreach 75 6d Recommendations for future activities 7 funding and manpower requirements 76 7a Cost and funding 80 7b Personnel and training

8 synthesis of the roadmap and final recommendations 82

annexes 86 Aa Contributors to the ARENA roadmap 91 Ab List of instruments at Dome C past, in operation, or being set up in 2009 92 Ac List of abbreviations

acknowledgements 95

references 95 Table of contents Table

4 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

5 . Executive Summary Executive

6 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Executive Summary

This document, prepared stronomers have always sought the the conditions on the Antarctic plateau. best possible observing conditions. ARENA created the impetus necessary to with the contributions of The inner Antarctic continent is the form international consortia in charge of Awildest, coldest, and driest desert on earth, preparing detailed studies (Phase A and B) more than 100 scientists offering an almost pristine nature without of at least a couple of the proposed pro- and engineers from Europe human contamination, or even faunal or jects; consortia that could possibly under- floral presence. It is therefore, in essence, an take their construction before the end of and Australia involved outstandingly appealing area to explore for the coming decade, 2010‑2020. the construction of major astronomical fa- in Antarctic astronomy, cilities of the future. Astronomers have for Preliminary site assessments and atmos- presents a roadmap decades been attracted by this opportunity. pheric modelling by several expert teams, Several pioneering attempts have been primarily from Australia, France, and Italy, for the development made to set up increasingly sophisticated have demonstrated that this region offers instruments over the last 40 years encom- exceptional conditions for astronomy of European astronomy passing a wide range of techniques and mainly thanks to the cold, dry, and calm and astrophysics in scientific goals. The only major astronomi- atmosphere. The atmosphere above the cal facility so far established is at the US highest spots of the Antarctic continent the Antarctic continent, station Amundsen-Scott, right at the geo- offers the best conditions on earth to and more specifically, graphic South Pole station, and named the investigate astronomical objects at high Martin A. Pomerantz Observatory in tribute angular resolution in the near thermal IR at the Concordia station to one of the most active astronomers in and submillimetre-wave ranges. The high Antarctica over the last half century. latitude location allows very long conti- (Dome C) in the coming nuous night-time photometric observa- decade (2010‑2020). France and Italy have recently joined the tions, which are essential for the study of effort: they have built and, since 2005, periodic variability of celestial objects. In It is based on the work operate year-round a multidisciplinary several well-identified domains («niches») station at Dome C called Concordia, one the Antarctic plateau may even compete carried out during of the highest domes on the Antarctic with space missions, but at a much lower the period 2006‑2009 Plateau, located about 1,200km from cost, and with the invaluable bonus of the sea coast at a latitude of about -75° using the most advanced technologies. within the framework and an elevation of 3,202m. Dome C is an extremely promising location for the The ARENA network has identified six of the ARENA network. establishment of the first European astro- particularly promising astrophysical areas nomical observatory in Antarctica, which with well-defined research programmes. eventually could become a major item of Taking into account the constraints of lo- international research infrastructure. gistics and environment, the network has been able to outline the top-level requi- To explore this opportunity in all its as- rements for the instrumentation able to pects, a network, ARENA, was created un- address these programmes. der the auspices of the European Com- mission. ARENA has had as a goal the They are, i) wide-field, extremely sensitive investigation of the scientific prospects imaging and spectro-imaging in the near of and the possibility of implementing an and thermal infrared (2.3-4µm) with a astronomical observatory at Concordia, 2.5m-class telescope (the PLT project), and to document a suite of instrumental ii) extremely sensitive submillimetre-wave projects that could benefit greatly from imager with a collecting area equivalent

7 .A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020)

to a 25m dish (project AST), iii) near IR beyond 2.3µm where observations are a catalogue of source calibrators in the interferometry for the detection of exo- normally hampered by the strong thermal far-southern sky, and attempt several planets and exozodiacal light (the ALAD- background emission of the sky from the science observations of the Sun and of DIN project), iv) a set of smaller dedica- ground. Thanks to the exceptional seeing star formation. ted instruments (some of them already conditions above the turbulent layer, Dome in the construction on-site) for planetary C is an ideal site to make large-scale, high Finally, this roadmap provides a vision transits, stellar variability, asteroseismo- angular resolution, extremely deep ima- for an Antarctic Submillimetre Telescope logy, and infrared imaging photometry, v) ging surveys in this wavelength regime. (AST) project. This could be a large teles- cosmic microwave background experi- cope facility consisting of a 25m diameter ments (the QUBIC project) and, vi) high The PLT (Polar Large Telescope) project class, single-dish at Dome C, or equivalent angular resolution solar measurements is the result of extensive discussions collective area achieved with a network (the AFSIIC project). between Europeans and Australians of medium-size radio telescope antennas, to propose a realistic, albeit ambitious, operating at submillimetre wavelengths A series of recommendations have been project for such a telescope with a and offering unique science possibilities. Its drawn from the discussions held during 2.5m aperture. A limited number of pro- perfomance at 200, 350 and 450µm would the several workshops and conferences grammes will be performed aimed at be superior to an equivalent telescope on that took place during the last four years. surveying very distant galaxies, dusty any of the Andean sites in Chile and Argen- SNIas, and extreme stellar populations tina. Furthermore, a single-dish telescope Site assessment in the local group, and at characterizing could be used as a Very Long Baseline A large amount of data have been collec- exoplanets by transit and microlensing Interferometry station with the ALMA and ted with the aim of quantifying the day milli-magnitude photometry. The project other antennas in South America. and night-time astronomical observing will be based on a European-Australian conditions at Dome C. The available data collaboration. A preliminary evaluation Optical and infrared interferometry show that the precipitable water vapour of the cost points toward a 11 M€ teles- Studying the warm inner parts of debris is usually below 0.7mm and drops to cope and 5 M€ focal instrument with a disks, the extrasolar counterparts of the 0.3mm for 50% of the time, thus offering Phase B study in 2010-2013 potentially zodiacal dust cloud, is of prime impor- excellent conditions for submillimetre funded by the FP7 and a first light before tance to characterize the global architec- observations. The extreme cold of the the end of the decade (hopefully 2018). ture of planetary systems. Furthermore, atmosphere means that its thermal emis- the presence of large quantities of warm sion is greatly reduced. This, in turn, leads Submillimetre-wave astronomy dust around nearby main sequence stars to significant savings in the time required Performing ground-based astronomical represents a possible obstacle for future to carry out large observing programmes observations in the submillimetre part of space missions dedicated to the direct de- at wavelengths longer than 2µm. the electromagnetic spectrum requires, tection and characterization of Earth-like at a minimum, very dry conditions. The planets. The frequency of the occurrence The absence of strong turbulence in the Antarctic plateau, a unique «desert» on of bright exozodiacal disks around solar- upper atmosphere results in low scintilla- Earth, is an obvious candidate site. type stars is currently mostly unknown. As tion and creates favourable conditions of today, exozodiacal disks have been di- for photometric programmes. The me- The atmospheric transmission in the sub- rectly resolved around a small number of dian free-atmosphere seeing in the visible millimetre windows centred at e.g., 200, main sequence stars, at a sensitivity level is 0’’.36, but achieving this imaging accu- 350, 450, and 850µm has been estimated of about 1,000 times our Solar System zo- racy in the optical is limited by the pre- by the team of CEA-IRFU/Saclay using diacal dust cloud. In this context, the An- sence of a very strongly turbulent boun- measurements with a tipper instrument tarctic plateau could provide the optimal dary layer which extends up to median and the MOLIERE radiative transfer mo- ground-based conditions for an infrared altitudes of some 40m in winter and up to delling code. The 200µm window opens nulling interferometer dedicated to the 400m in summer. The small outer scale of up to better than 20% transmission for direct detection of warm dust clouds turbulence measured at Dome C, combi- 25% of the time. Observations at 350 and around nearby main sequence stars. ned with a long coherence time and with 450µm would be possible all year. These the large isoplanatic angle is beneficial values of transmission indicate that obser- Joint efforts between several European for high angular resolution techniques ving conditions at Dome C are superior to institutes within the ARENA consortium at this site. Detailed measurements of the the known sites in Chile or Argentina. The led to the definition of the ALADDIN vertical and temporal variation of the estimated transmission values were used concept. In order to achieve a signifi- atmospheric parameters are now needed, as filters to select science cases. The «Cos- cantly improved sensitivity with respect in order to draw robust conclusions about mic history of star formation, black holes to existing instruments, the architecture short- and long-term stabilities and trends, and galaxies», «Origins of stellar masses», of the system is specifically focussed and to constrain the specifications of ins- «Galactic engines», and «Galaxy clusters and optimised for the purpose: ALADDIN truments to be deployed at Dome C. in the far Universe and dark energy» implements the nulling interferometry were selected as the four main topics of technique at the focal plane of a two Near-infrared high angular science cases for a submillimetre-wave telescope interferometer mounted on resolution wide-field imaging telescope facility in Antarctica. a rotating beam structure. Thanks to the Various countries have for some time Antarctic environment, such a nulling in- proposed the construction of a large One of the functions of the thermal infra- terferometer coupled to a pair of 1m-class optical/infrared telescope in Antarctica. red telescope (the Italian IRAIT 80cm) telescopes operated at thermal infrared The conditions on the Antarctic plateau can be as a pathfinding experiment for wavelengths would perform significantly particularly favour an exploitation of the submillimetre astronomy. It will perform better than a similar instrument working spectral windows not easily accessible atmospheric and sky-noise measure- on 8m-class telescopes in a temperate

Executive Summary Executive from the ground, i.e., in the thermal IR ments with a bolometer array, prepare site (e.g., at ESO Paranal). 8 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Long time-series in 1965 by Penzias and Wilson and it has These data include direct measurements photometric observations been demonstrated that Antarctica is the of the magnetic field in the chromosphe- Time-series data are the result of astrono- best place on Earth to study its anisotro- re and corona made possible by exploi- mical observations of temporal pheno- pies in temperature and polarization. The ting the remarkable infrared atmospheric mena; to be valuable such observations US M.A. Pomerantz Observatory at the transmission on the Antarctic plateau. typically require one or more of the fol- South Pole is essentially dedicated to this Accordingly, primary science cases were lowing conditions: research with, today, the largest astrophy- defined in both high angular resolution • Long observing duration coverage in sical instrument ever built on this conti- and 2D coronal spectroscopy and a me- stable conditions, particularly in combi- nent, the South Pole Telescope (SPT), a soscale facility, has been designed to nation with high duty cycles 10m aperture millimetre-wave dish and achieve them. • Very good seeing and/or low scintillation the BICEP polarization experiment. The • Observations in spectral ranges that basic advantage of the polar environment The project proposed the Antarctica Fa- have been little explored to date. for CMB research is the unique atmos- cility for Solar Interferometric Imaging pheric stability, particularly of the Earth and Coronagraphy (AFSIIC), a large (by Contributing to all of these requirements, atmospheric molecular oxygen lines, and solar astronomy standards) assembly of Dome C provides unique opportunities the fact that one can observe the same 3xØ500mm (preferably Ø700mm) off- for ground-based observations. Because area of the sky over very long periods axis SiC telescopes placed above the tur- of the need for long and continuous time at almost constant elevation. Dome C bulent layer. With a baseline of 1.4-4m this coverage, most such observations require appears to be even better because of a solar interferometer with coronal capabi- a dedicated telescope, typically of sub- lower atmospheric optical depth and of lities would have a performance superior 1m size. However, there are also scientific lower wind speeds, and thus even better to any current or planned ground-based cases for which the use of significant time stability (with respect to the South Pole). telescope, including the 4m-class ATST allocations on larger multi-purpose facili- Moreover, its location 14° in latitude away and EST. It features 2D spectro-imaging, ties is more appropriate. The major scien- from the pole allows cross-linked scans spectropolarimetry, magnetoseismology, ce cases for time-series at Dome C are: de- and drift removal techniques. and chromospheric and coronal magneto- tection and characterization of extrasolar metry to facilitate a magnetic investigation planets (transits), asteroseismology, and Members of the CMB working group are from the convection zone to the corona. stellar activity studies. The panel reviewed currently implementing the QUBIC expe- Furthermore, it will be the only major solar several projects that were presented: riment through a collaboration between observing facility in the southern hemis- • ASTEP 400, a 40cm telescope for planet Italy, France, Ireland, UK and the USA. This phere, observing when other (northern) detection, received its first light in Novem- instrument (formerly called BRAIN) will telescopes will suffer from winter conditions. ber 2009. It should provide scientific data take advantage of the conditions at Dome rapidly (2010-2011) and thus ought to be C to mainly measure the B-mode of the ARENA roadmap strongly supported by the relevant agencies. CMB polarization with a bolometric in- Considering the various propositions • Of projects in the development phase, terferometer combining the extreme sen- made by the working groups and on the ICE-T (International Concordia Explorer sitivity of bolometric detectors with the basis of the present knowledge of the site Telescope), a 2x60cm binocular telesco- optical purity of interferometers. The pro- assessment, the following statements and pe, is graded the top priority instrument ject is supported by IN2P3 in France and recommendations are made by the ARE- for time-series photometry; it is expected PNRA in Italy and by the ARENA CMC. NA CMC. We recommend that a process to become the reference instrument for be fostered to lead to the creation of an stellar activity studies. Its construction is The working group also supports a project internationally managed astrophysical funded, but site-access and operational for a single millimetre and submillimetre- station at Dome C aimed at collecting issues need to be resolved as soon as wave large dish mainly for high angular unique data over a wide range of wave- possible for an anticipated deployment resolution observations of intra-cluster lengths from the visible to the millimetre. around 2013-2014. structures and the study of the different We strongly recommend continuation • SIAMOIS (Seismic Interferometer Aiming populations of thermal and non-thermal of the site quality characterization to to Measure Oscillations in the Interior of electrons that produce distinct Sunyaev- confirm the promising results already ob- Stars) is the top priority instrument for ad- Zel’dovitch effects (SZE) and that could tained, and to study their variations with vanced time-series spectroscopy, and is ex- provide new clues on Dark Matter candi- time. Atmospheric parameters that have pected to become the reference in stellar dates. thus far not been fully studied should Doppler velocity studies. Its deployment be measured and monitored with some with two small-aperture telescopes is an- Solar astrophysics urgency. These include: the atmospheric ticipated for 2013-2014. In a second phase, The Concordia station also offers unique opacity at all wavelengths, the photome- the scientific return can be enhanced to qualities for solar observations, combi- tric stability, the sky background emission include specific faint targets by feeding ning excellent seeing, low coronal sky bri- (particularly in the near thermal infrared) the instrument from a 2m-class telescope. ghtness, low water vapour content, conti- the turbulence profile and the outer sca- • Finally, PLT (Polar Large Telescope) is nuity and an impressive duty cycle (four le of turbulence. We strongly recommend considered critical for shorter time-series months, i.e., three times more than at mid- making these data rapidly available to projects requiring a larger and flexible latitudes sites, under excellent observing the community and implementing a re- instrument, where open access for the conditions). This allows both to perform gularly updated data-base to archive the scientific community will be important. very high angular resolution (<< 0’’.1) data and provide long-term, easy access adaptive optics observations and access to them. We strongly recommend using, Cosmic Microwave Background to the corona, thus providing data on as far as possible, the same instruments, Cosmic Microwave Background (CMB) the chromosphere-corona interface that calibration, data processing in the diffe- observations have been extensively deve- is impossible to obtain from other sites rent polar sites currently under investiga- loped since the discovery of this radiation (or indeed from space for many years). tion, to enable objective comparison. 9 .A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020)

We express our interest in the explora- - an instrument dedicated to high angu- astronomical sites on the Earth, operated tion of as yet undocumented sites (such lar resolution astrophysical studies of the all year round. Concordia is, in principle, as the Antarctic Ridges A and B). Sun (such as AFSIIC). ready to implement, host, and operate a new generation of mesoscale astrono- We have identified a wide range of scien- It is unlikely that all these actions will mical instruments capable of major ad- ce cases, as detailed above, that would be funded in the next decade, but, after vances in several cutting-edge astrophy- strongly benefit from the unique Antarctic deliberation in the CMC, ARENA refrains sical areas during the next decades. The conditions. A suite of appropriately desi- from ranking these projects, leaving these momentum created by ARENA should gned instruments is identified; these can strategic decisions to the national, euro- definitely be sustained through new vi- be classified into three main categories: pean, and international agencies that are gorous actions, such as a better coordi- • small instruments, some of which are expressed, for instance, in the body of the nation of the site testing operations and currently in the construction phase (IRAIT, ASTRONET recommendations. data access, the establishment of consor- COCHISE, BRAIN/QUBIC, TAVERN, AS- tia to submit excellent proposals to the TEP) or ready to be built (SIAMOIS, ICE-T). However, we believe that the only project relevant funding calls, and above all the They all fit within the present logistics ca- in the mid-size (cost) range that can effec- Phase B study of mesoscale projects. This pabilities. Their cost is in the range of a tively be carried out in the next decade should be followed with firm decisions few million euros. For obvious reasons of is PLT. This project has the potential for a by the national agencies. manpower capacity on site, and to leave wide support from the community and room for more ambitious projects, their will be made possible only if a strong and An accompanying public outreach pro- number should not increase without sustainable international collaboration is gramme is essential and should be set limit in the future. An international peer- set up around it. up. A culture of cooperation between reviewing process to select future pro- the management of the different stations jects based on their scientific excellence We point out that several studies that will currently in operation is also highly desi- should be established, be carried out for this project, such as the rable. Ultimately, we propose the creation • mid-size facilities (mesoscale projects, implementation of a Ground Layer Adap- of a European Centre for Astrophysics in cost range of a few tens of millions tative Optics (GLAO) device specific to Antarctica on the model of existing mul- euros, (such as PLT or a solar telescope/ polar conditions, the construction of a tinational organizations. . interferometer) that will need affordable stiff tower and the mitigation of frosting, upgrades of the logistics (power supply, will also be useful for other projects, in transport, e-communication). They will particular future optical/IR interferome- The ARENA CMC, require, however, a very large deployment tric and solar projects. December 2009 of personnel to the site over several summer seasons for the construction, Fostering European and international • large to extremely large projects that, collaborations and aggregating a critical according to the conclusions of the dedi- mass of resources have been constantly cated ARENA activity NA4 would require emphasised during the ARENA meetings. a sufficiently large increase in the resour- Although ARENA has helped in initiating ces available for logistics that one could some successful common work, the pre- not expect to be deployed in the coming sent situation is far from being satisfac- decade (such as ALADDIN, AST, AFSIIC tory. In particular there is clearly a deficit and, a fortiori, KEOPS - the km-scale opti- of collaborative programmes between cal/infrared interferometer array). institutes belonging to the two countries of Concordia. Additionally, there is little For the coming decade and in conside- doubt that an emphasis on small projects ration of the reflections of the different does not encourage wide, long-term col- working groups the following recommen- laborations. The internationalisation of dations of ARENA are made: Concordia for astrophysics to the status of a European Research Infrastructure is es- • to continue the site assessment sential, but it is strongly dependent on the • to establish a major funding plan in decision to build at least one significant order to run the currently on-going teles- ambitious project, now, and to propose an copes or instruments (COCHISE, IRAIT, ambitious vision beyond. Our conclusion ASTEP, BRAIN) and obtain as soon as is that, without vigorous support from the possible high-quality science from them national and international agencies and • to make plans for the rapid implementation agreements between them, the astronomi- of SIAMOIS and ICE-T cal potential of the station will not deve- • to start immediately, in 2010, a phase B lop even though it is located in the best study for PLT on the basis of the phase A astronomical site on Earth.This would studies made by the Australians for PILOT, constitute a major paradox precisely at for first light before the end of the decade. the time when China is creating an An- • to commence phase A studies for: tarctic Astronomical Centre at Dome A. - a large submillimetre-wave telescope facility (AST) to exploit the extraordinary In conclusion, we consider that the potential of the site in the THz regime, Concordia station at Dome C represents - a pathfinder for interferometry in the a real opportunity for Europe (and col-

Executive Summary Executive optical/NIR range (such as ALADDIN) , laborators) to develop one of the best 10 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

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1 Approach and Scope 1a Context

The Antarctic Plateau stronomers have consistently sou- seismic or volcanic activity. The nearest ght geographical locations that significant source of industrial pollu- offers exceptional provide the best conditions for tion is more than 5,000km away and Atheir observations: the largest fraction of the pattern of atmospheric circulation atmospheric and time that the sky is clear, access to the is such that very little pollution is intro- environmental conditions broadest spectral range, the highest trans- duced into the atmosphere above the parency, the best seeing and the lowest Antarctic plateau. It is therefore, in es- for astronomical sky brightness, minimal contamination sence, an outstandingly appealing area by dust, light, or aerosols. A powerful, but to explore for the establishment of ma- observations over a wide expensive and limited solution is to set up jor astronomical facilities in the future. range of wavelengths. instruments above the lowest layers of the Astronomers have been attracted since Earth atmosphere using balloons, airpla- decades by this opportunity and have The ARENA network nes, rockets or satellites. made several pioneering attempts to set up increasingly sophisticated instru- has investigated However, space platforms have never ments during the last 40 years. Only one the various scientific, replaced ground based astronomy. It is significant spot has been implemented currently, and most likely will remain so at the US station Amundsen-Scott, right technical and practical for a long time to come, necessary to use at the South Pole, so far, the Martin A. Po- issues relevant to the ground-based facilities to achieve extre- merantz Observatory named in tribute mely large collecting areas and in parti- to one of the most active astronomers creation of a world class cular to be able to use state-of-the-art ins- in Antarctica since 1959. The recent ope- trumentation that can be upgraded on a ning all year long of the French-Italian international observatory regular basis. Interferometry, for instance, Concordia station at Dome C is a major in Antarctica. is unlikely to be performed from space opportunity for Europe to participate in in the next decade. The search for the this challenging adventure. best ground based site remains topical, although the Chilean Andes and Hawaii Concordia plan: are currently viewed as the best facilities exploded view currently in use. There might be, however, of the Concordia even more attractive locations - for ins- station tance on the Antarctic continent.

The scope of the present document is to propose a decadal plan for the development of Antarctica as a platform for a new type of astronomy. It is the result of a common reflection and thorough investigations in different astrophysical areas of about one hundred experts: researchers and engineers in astrophysics, atmospheric physics, instrumentation and polar logistics.

The inner Antarctica is indeed the wildest, coldest and driest desert on Earth. It offers Stations an almost virgin nature without human, fau- in Antarctica nal or floral contamination, and negligible

13 14 Approach and scope . publication andcitation rates. high very achieve routinely (CFHT), cope Canada-France-Hawaiithe Teles(SDSS), or - Survey Sky Digital Sloan the for used cope sky,the veysof teles- Sloan 2.5m the as such sur to dedicated telescopes Indeed,cost. modest relatively at data essential provide to continue still will centres archiving and instruments and linked to powerful pipeline suitably focal art located,state-of-the with equipped are they provided diameter, ters me- few a to 1 from spanning range the in Telescopes conditions. atmospheric stable areas, collecting butrather, extremelyor time observing long large very require sarily neces- rements.not do investigationsThese measu- polarization CMB and corona solar jects, high angular resolution of the Sun and ob- variable of monitoring resolution time (surveys),high areas multispectral sky large of mapping the are investigations sical astrophy- essential such resolution.Among angular or sensitivities extreme require not do that phenomena astrophysicalvestigate in- to astronomers for tools essential be to continue will telescopes smaller truments, Besides these extremely large and costly ins- the possible emergence oflife. of the Universe since its beginning very to evolutionthe of understanding the in ghs will undoubtedly yield major breakthrou- and decade next the during operational fully be will instruments these frared.All mid-in- the to visible the of from sensitivity level unprecedented an the at Universe probe will Telescope Space Webb James 6m the space, From thereon. life of traces identify possibly and exo-Earths in the Universe), identify and characterize light (first galaxies distant most the study to one allowing resolution angular high very and sensitivityexceptional offer will instruments gigantic These range. wave by ALMA for the millimetre/submillimetre and range, optical/infrared the TMT/for American the such and European-ELT the telescopes as giant the of by decade construction next the in dominated be clearly will astronomy based Ground Winterover staff2008 A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) - towers (2006) Concordiastro The

ae og rvn hi eclec but, excellence their proven long have Paranal,(Cerro Andes Chajnantor) Cerro Chilean the and Kea) (Mauna Hawaii in sites operatedtropicalcurrently best The natural,or origin,it.aboveanyhuman of sea level and the absence of sky pollution is basically governed by its altitude above transparency,turn atmospheric in which the on depends strongly operated fully particular spectralwhichrangethe in use- be can it in telescope, any of success the to essential is location site Excellent immense databases as “legacies”. providing mode, dedicated “survey”the moved successfullyinto have been CFHT telescopes,class Several2-4m the as such pipeline that their operators cannot afford. data or equipment focal system, control their of upgrading require wouldsites, or outstanding from operate tions,not do or them are not suitable for “survey”- observa telescopes are in operation across the world, 2-4m many of of number a Although Winterover staff2009 h acs t ohrie unobservable spectral lines or bands of major astrophy otherwise to access the or conditions photometric stable more lines or molecular bands) allowing much absorption undesirable of or (free cleaner broader significantly become usual ones the and open, windows spectral Mauna Kea). Under these conditions, new than the best currently exploited IR site at less times 10 to (5 lowextremely is vapour water atmospheric of density lumn co- the -80°C),and to (-30 to 4,000m),cold (3,000 high is plateau Antarctic The ghest, coldest, hi- andmoststable driest sites. the at observatories of constructions requires value science resulting thus,the and,conditions observing the Improving lines (such asOHinthenearinfrared). emission radical and molecular sirable sky background emission and thermal by some unde- infrared their by parency, trans- infrared/submillimetre lowlatively re- their by limited remainnevertheless, - A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

sical interest just at the edges of the usual atmospheric windows. Moreover, Antarc- tica has a unique political status on our 1b Brief historical planet:it is a continent exclusively dedicated to scientific research under the protection of international treaties (the Antarctic Treaty and the Madrid proto- overview col) preserving the entire continent from all sorts of future undesirable human pollution. It is therefore, in essence, a model for international collaborations. early a century ago, in 1911, the in 1961. With this treaty, “freedom of scienti- In addition, because of its high latitude Norwegian Roald Amundsen rea- fic investigation in Antarctica and coopera- range, the long duration of dark time ched the South Pole. As early as tion toward that end, as applied during the allows long duty cycle observations N1912, the American polar explorer Robert International Geophysical Year, shall conti- particularly suited to a continuous pho- E. Peary had the intuition that the privi- nue, subject to the provisions of the present tometric sampling of variable pheno- leged geographical position of the South Treaty’’ and “Antarctica shall be used for mena such as stellar pulsations (astero- Pole could be suitable for astronomical peaceful purposes only. There shall be pro- seismology), or periodic events such as observations. Today many results cove- hibited, inter alia, any measure of a military planetary transits. ring a wide field of interests from star nature, such as the establishment of mili- formation through solar physics to the tary bases and fortifications, the carrying Finally, the structure of the atmospheric analysis of the CMB have been obtained out of military manoeuvres, as well as the turbulent layer is such that the “free” at- from Antarctica. Ambitious projects to testing of any type of weapon’’. Moreover, mosphere begins relatively close to the create an observatory are under conside- in order to pursue the effective scientific ground, from a few to a few tens meters ration at Dome C thanks to the successes coordination of IGY, the Scientific Com- altitude. This particular behaviour of the obtained with earlier polar astronomical mittee on Antarctic Research (SCAR) is boundary layer and of the key parame- experiments developed during the pre- created in 1958. ters that govern high angular resolution vious half century. imaging in the optical and near infrared brings an additional incomparable advan- Windows into geospace tage of Antarctica over conventional sites. In 1955, Antarctic astronomy started with non conventional telescopes when Creating an astronomical observatory the Australians installed their cosmic in Antarctica has been dreamt of for de- ray observatory at the Mawson coastal cades in several countries and the USA station. The collisions between cosmic have effectively established a major ob- rays and atmospheric molecules create servatory at the geographical South Pole particle showers, especially muons and making use year-round of the Amund- neutrons. This cosmic radiation also gi- sen-Scott station. The M. A. Pomerantz ves birth to many phenomena located Observatory is now mainly dedicated in the upper atmosphere: auroras, ioni- In 1959, Americans began a cosmic ray programme to millimetre wave astronomy - and in zation of the atmosphere, etc. Thus the research in Antarctica. They installed a neutron particular to CMB measurements. It is polar regions constitute a unique place detector developed during the IGY at the McMurdo in continuous development and has re- to observe the geomagnetic properties coastal station inside the Cosray building standing cently received a new large millimetre and the interactions between the Earth here in the middle of the picture. wave instrument consisting of a 10m and the interplanetary medium. In the diameter dish (South Pole Telescope). 1950s these geophysical issues pushed This international cooperation was a real the ICSU (International Council of springboard for the cosmic ray measure- However, this station is not particularly Scientific Unions) to launch an - inter ments from Antarctica. In 1959, just after suited to shorter wavelength astronomy national cooperation programme, the the IGY, the recently opened Office of Polar because of the relatively small frac- International Geophysical Year (IGY). Programmes of the US National Science tion of clear sky, and a relatively thick Foundation (NSF) puts Martin Pomerantz boundary layer resulting in poor seeing IGY is a major milestone in the history of in charge of installing one of these detec- conditions. On the other hand, sites polar exploration and particularly in An- tors at the US McMurdo coastal base. In located on “Domes” that dominate the tarctic research. Building up on the model 1964, he installed neutron detectors at the plateau and away from which flow the of the previous polar years (in 1882-1883 South Pole too. These detectors, both in katabatic winds are much more appea- and 1932-1933), the IGY lasted from July the Arctic and Antarctic allowed for the ling for optical, infrared and submilli- 1957 to December 1958. The IGY was not first time simultaneous measurements metre observations. restricted to the polar regions and, by the from the two hemispheres of solar cosmic end of 1958, 61 countries were finally in- rays and a very precise characterization It has been the purpose of the ARENA volved in this worldwide collaboration. of the heliosphere. Pomerantz’s team also network to conduct studies and to pro- IGY stimulated unprecedented develop- initiated balloon launches with instru- duce documents covering all aspects ments of polar logistics and the construc- ments on board to detect X-rays above An- relevant to the creation of this « Observa- tion of about fifty bases inside the conti- tarctica from McMurdo. Thus, in 1969 and tory of the Future» at the station Concor- nent or along the Antarctic coast. As a 1970, they discovered serendipitously the dia in coordination with other roadmap consequence of IGY the Antarctic Treaty unique possibilities of long lifetime bal- exercises such as ASTRONET. . was written, then ratified by 12 countries loon-borne flights above Antarctica. 15 16 Approach and scope . ning ofphotonic astronomy in Antarctica. discipline, new helioseismology, a begin- the and of birth the marked observations than 80 resonance modes of the Sun. These more distinguish to them enabled ments of observations of the Sun. These measure- days full achievedobjective: uninterrupted their six They funding. American with 1978-1979 summer in installed was ment - instru Nice.Their Grec, from Gérard and Fossat Eric hours, 24 than longer periods uninterrupted observations out of the Sun over carry to proposed who astronomers solar French young two with laboration col- a later, started Pomerantz years Eight was officially presented andpublished. Antarctica in astronomy for potential the Pole for astronomy. This is the first time that vocating the unique potential of the South of the US Academy of Sciences in 1970, ad- researchforpolar committee the report to inch telescope convinced Wyller to write a 5 a with 1968-1969 in made Observations temperatures.cold and sky vation,clear a ele- source observations:constant solar a out carry to place unique a wouldalso be Pole South the that noted ler, Pomerantz Wyl- Arne astronomer Swedish the sicist, phyWorkingsolar - a collaborationwith in in Antarctica photonic stepsof astronomyFirst . our universe isflat (seeChapter4e) that showed measurements, which gical cosmolo- unique out carried experiment this flight, of 10-days a one after 1998, In them. is experiment Geomagnetics) and Radiations Extragalactic Millimetric of Observations (Balloon famous BOOMERanG The McMurdo. from launched Every latitude. summer since 1988, same two flights have been the while at days remaining can several balloon throughout the follow that vortex a create continent the above streams thermal ric summer,Antarctic atmosphe- the During damental resultsincosmology. experiment launched in 1998 and which gave fun- BOOMERanG famous the Here,Antarctica. above more or days 10 during fly can balloons these tex, vor polar launch summer the Using to balloons. flight long station coastal McMurdo the of tage advan- take astronomers 1988, since year Every A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020)

- necessary tocooldown thedetectors.necessary tics allows the supply of the liquid helium cellent millimetre-wave site and the logis- for astronomy at the South Pole: it is an ex- demonstrated. success double a thus is It Pole over Mauna Kea in this field was thus atmospheric South the the fluctuations. of superiority The by limited were they Hawaii, in Kea Mauna at limits, whereas instrumental reach to found were ments was a success. At the South Pole, experiment measure The- summer. 1984-1985 the during range submillimetre-wave the in emission centre galactic the , measured ) Millimétrique (Emission EMILIE ment, Orsay.from Puget Jean-Loup - instru Their the in of team domain,submillimetre-wavethe team French reputable called a Pomerantz upon 1975. in Pole the at South PWV the of measurements nary prelimi- first the by confirmed was there.This low extremely is range, tre-wave millime- the and infrared the in opacity atmospheric of source main (PWV),the content vapour water conditions. precipitable The Antarctic the also from could astronomy benefit of fields Other potential of Antarctic observations. mostlysceptical, about extraordinarythe community,astronomical the of ception observationslar deeply changed per the so- of success the that doubt no is There 1994. in ended programme Obser vatory).The Heliospheric and observatory (Solar space SOHO solar the of on board was helioseismology to dedicated Network instrument an Oscillations and createdwere Group) (Global GONG results, (International and Sun) the IRIS of Interior the of Research historical as such networks these Following out preliminary measurements.out preliminary carry to instrument an up Pernicset bert by Anthony Stark, Mark Dragovan and Ro- 1986-1987, a team from ATT Bell Labs lead the cosmological background. In summer influctuations temperature tiny the ting investiga- were who CMB in experts the by understood immediately was nomy astro- millimetre-wave for potential This Page, M. Pomerantz, E. Fossat). helioseismology.L..of Grec, G. right: to left(From during 6 days at South Pole. This was the beginning ricancollaboration observedcontinuouslySun the FrenchA observations. Ja- solar Ame with 1980 nuary in started Antarctica in astronomy Photonic - - - ladder -, J.C. Renault). ladder -,J.C.Renault). get, R. Gispert, J.M. Lamarre, C. Maurel - behind the astronomy.Pu (Fromupperrighttoleft:J.L. Antarcticaofplateausubmillimetre-wave highfor riment. This instrument demonstrated the potential expe- EMILIE the with Pole South at 1984 cember de- in place took collaboration French-American A on thehighplateau. conditions atmospheric the of idea listic data allowed the community to get a rea- altitude of 3,500m) and at Dome C. These base since 1975), at Vostok (located at an at the South Pole (called Amundsen-Scott collected data meteorological on based was Antarctica in as- potential the tronomical of evaluation the 1980s, the In the Antarcticplateau on Super seeing conditions such from alongperiod theground. over made were observations terrupted Velorum. This was the timefirst that unin- as such stars variable of observations of hours uninterrupted 16 1986, in ned, obtai- visible,which the in 8cm of cope teles - small a Telescope), Optical Polar South (the SPOT by achievedwere tions - observa continuous Meanwhile winter. Antarctic during measurements perform to telescope first the was 2.60m-antenna Infrarosso E Submillimetrico Antartico (Osservatorio OASI antenna metre-wave submilli- the 1986 since there installing by station Zucchelli) Mario (now Nova Terra their at Antarctica recognised of potential also the Italians side, their On Pole observatory. South the of predilection of themes the mological background constitutes cos- one of the of measurement accurate The

). This g 2 - A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

After the solar and millimetric observations at the South Pole, and the Italian initiative at Terra Nova, Australians showed their interest in the potential of an astronomical site located so close to their country. During the second half of the eighties, Peter Gil- lingham suggested that the extremely low temperatures and the atmosphere stability could lead to the unique potential for high angular resolution observations on the high plateau; he spoke about “super seeing”.

Following an initiative of Pomerantz, more than 100 astronomers interested in the astronomical potential of the high Antarctic plateau were invited to a conference at the Bartol Institute in June 1989, “Astro- physics in Antarctica”. This meeting leads to a real American scientific policy which durably influenced the “astrophysical” The Amundsen-Scott station has developed a large area entirely dedicated to astronomical observations (essentially cosmologi- conquest of the highest spots of the pla- cal background observations and neutrino detection) free from electromagnetic perturbations: the “dark sector”. (In the upper teau. During this meeting, the idea to crea- left: SPT and BICEP; in the upper centre: the M. Pomerantz Observatory; in the middle: the IceCube laboratory; the red drills te a Centre for Astrophysical Research in are the summer camp for icecubers). Antarctica (CARA) is put forward. This centre was officially founded in 1991, it The international astronomical commu- is headquarted at the Yerkes Observatory nity recognized the astronomical potenti- (University of Chicago) and gathers seve- al of the Antarctic plateau during the 21st ral American universities. With an optimi- IAU Assembly in Buenos Aires in 1991. zed logistic organisation for astrophysics, A session dedicated to Antarctic astrono- the goal of CARA is to achieve four main my was organized and the IAU recognizes projects: SPIREX (South Pole Infrared Ex- “the fact that the extremely dry, cold and plorer), a 60cm telescope specially deve- tenuous atmosphere above the Antarctic loped to probe the deep sky between 2 plateau provides the best observing condi- and 3µm and to assess the infrared poten- tions on Earth in the infrared wavelength, tial of the site; AST/RO (Antarctic Submil- submillimetre and millimetre wavelength limetre Telescopes and Remote Observa- range” and in particular resolves “to create tory), a 1.70m submillimetre-wave antenna a working group to encourage internatio- to probe the carbon line around 600µm in nal cooperation in site testing […]”. Se- our Galaxy and in the Magellanic Clouds; veral meetings took place in France and COBRA (Cosmic Background Radiation in Australia between the site testing spe- Anisotropy), a 0.75m telescope to detect cialists of the University of Nice and the the temperature fluctuations of the CMB University of New South Wales. A collabo- up to angular scales of 20°; and finally ATP ration was established in 1993 between Al (Advanced Telescope Project), a collabo- Harper (CARA), Peter Gillingham (UNSW) One of the major results of the infrared telescope ration between American and foreign ins- and Jean Vernin (University of Nice). SPIREX set at the South Pole is a survey of the NGC 6334 nebula in the near infrared range from titutions to evaluate the site quality for as- 2.42 to 4.8µm taken in 1998. This wide-field survey tronomy and to prepare a larger telescope Temperature measurements were carried (30’) acknowledged infrared potential of Antarc- in the infrared and in the submillimetre- out in 1994 at the South Pole with micro- tica to study such star formation regions with high wave for the end of the 1990s. thermal sensors installed on a 30m mast, angular resolution. then in 1995 with 15 balloons instrumen- This conference also gave rise to a propo- ted with microthermal probes. first time at the conference, “Polar Re- sal of John Lynch, the NSF program ma- search: a strategy for the year 2000” held nager for Aeronomy and Astrophysics, for These first measurements confirmed Gil- in the French Académie des Sciences in the construction of an international sta- lingham predictions: the seeing in the Paris in 1992. The selected site sets at tion on top of the high plateau. This station visible is quite poor, but turbulence is Dome C, located about 40km away from would be a pathfinder for a lunar station, essentially concentrated in a thin layer the site where the glaciologist Claude then under discussion in the space agen- localized in the first 200m above the Lorius and his team have extracted an cies. More precisely, this station would ground. On top of the plateau, where the ice core sample in 1978. Paleoclimato- have a strong “astrophysical” colour and winds are lower and temperatures col- logy is one of the main scientific drivers would be located at 4,000m above the der, this turbulence layer may be even for the establishment of this 3rd perma- sea level. At the end of the 1980s, the An- thinner. It is what is actually observed at nent base on the inland, after Amund- tarctic domes are estimated to be the best Dome C (nearly 30m). sen-Scott and Vostok. ground sites for infrared, submillimetre This became in 2004 with the record ex- and millimetre-wave astronomy as well Towards an observatory at Dome C traction of a 3km long ice core giving in- as Earth-Sun interactions study, due to the The construction of the French-Italian formation on climatic variations during proximity of the magnetic pole. Concordia station is mentioned for the the last 800,000 years (EPICA). 17 18 Approach and scope . COCHISE antennasetatDomeC. the currently is priority PNRA the but operational cope to operate during winter. This antenna is still teles- Antarctic first the was and station Zucchelli metre-wave range. It has been set in 1987 at Mario OASI telescope is a 2.60m antenna in the submilli- 2007-2008 Summer Campaign 2007-2008 mospheric turbulenceaboveDomeA. installed automated instruments to measure the at- achieved two campaigns in 2005 and 2006 and they already have They level). sea the above (4,040m A Domebackgroundleft)atthe the yel- in on one low and red (the station Kunlun the of first building the inaugurated Chinese 2009, February In of the half constructed Concordia station. front in fluctuations atmospheric observed astronomer an 2002, in Here February). to December (from paigns cam- summer the during only led be could observations testing site 2005, in winterover first the to 2000 From A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) the SouthPole from 1997 to 2003. at installed for Antarctica) Observatory cal Astrophysi(Automated- AASTO of version improved an Observatory).is ternational It In- Testing Site Astrophysical (Automated AASTINO year: whole the during sky the of quality the characterize to station matic auto- an Concordia at set Storey John by This is why in 2003 the Australian group lead thepolarnight.done during pleted,be not could measurements these com - not was station the of construction the as year.long each as February But to December from installed missions summer during are purpose this to dedicated instruments Many C. Dome of characterization systematic a in consists LUAN) toire Universitaire d’Astrophysique de Nice, (Labora- Fossat Eric by lead programme Concordiastro 2000,the problems.In tics logis- of because of stopped was Concordia construction the 2000, content. to 1996 vapour From water precipitable ric atmosphe- the measuring by C Dome characteristics of submillimetre-wave the atOASI Terra with rience Nova, evaluated ( ( Valenziano Luca Italians, two 1995-1996, In visible. the in turbulence atmospheric characterize to Pole South the from those as measurements of type same the out carry to C Dome from balloons ched 1995,as Jean soon Vernin’s As laun- team for astronomyin2010. plateau.Japan plans tobegin site testing campaigns red as one of the best sites for astronomyconside- onis thelevel) highsea the above (3,810m Fuji Dome Università La Sapienza), using their expe- Dall’Oglio Giorgio and INAF, Bologna) It was the beginning of the site testing campaigns. C. Dome to go to astronomers first two the were picture) the took who one (the Vernin Jean and red) in left the (on Dall’Oglio Giorgio 1995, In po M 1916-2008 at the SouthPole. at his26missions of the last was It A.(Martin Pomerantz Observatory). the CMBobservations: to MAPO the buildingsdedicated one of the SouthPole at in1995 contribution, NSFinaugurated this exceptional In honourof background, neutrinodetection… cosmological microwave in various domains: solarphysics, several astrophysical collaborations location for astronomy, heinitiated the SouthPole that isanideal the SouthPole in1964. Convinced to then McMurdoto in1959 him polar led experience This first the Arctic(Groenland).in speciality, drove to him Thule, cosmicof rays, hisprimary Geophysical Year, the study the InternationalDuring Delaware). of Institute (University Researchthe Bartol career at Pomerantz didallhisscientific South Pole, Arthur Martin the in Antarctica andmainlyat the development astronomy of of Considered the leaders asoneof ar mer t in ar in an t z t hur

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Mario Zucchelli 1944-2003 1c How ARENA Mario Zucchelli was one of the main figures of the Italian Research programme in Antarctica. worked With an initial training as nuclear physicist, he was appointed director in 1975 of the most important Italian nuclear research center until he project to gather skills and re- tor strived to adjust the work programme 1987, the Brasimone Research sources of several European and according to the most recent site testing results, and to welcome new expressions Centre. Then he was appointed Australian laboratories to imple- Tment an international astronomical obser- of interest to join the network. The origi- director of the Antarctica Italian vatory at the Concordia station Dome C nal work programme was amended seve- programme for which he lead 15 came into existence in the early 2000s. ral times and after the Mid Term Review, expeditions until his death in 2003. It was basically motivated by the extensive in 2007, the contract was extended for site testing experiments made by various one year (2009). Originally dedicated to During these 16 years, he initiated laboratories in France, Italy and Australia, optical and infrared astronomy, it moved several international collaborations: the important involvement of the Italian toward a wider scope including cosmic for instance, the ice coring European community to set up an infrared telescope microwave background experiments, mil- programme EPICA or the French-Italian (IRAIT), and the desire to implement opti- limetre wave astronomy and solar phy- cal/IR interferometric arrays and to access sics. ARENA encompassed most of the agreement signed in 1993 for new spectral windows in the thermal infra- astronomical activities that are already, or the construction of the Concordia red and Terahertz ranges. The exceptional could be, carried out in Antarctica, as well station. To honour him, PNRA seeing conditions measured above a thin as some aspects of atmospheric physics directly linked to astronomy. decided in 2004 to give his name turbulent layer of a few tens of meters stimulated the high angular resolution and to the coastal station of Terra Nova, interferometric communities. The exceptio- The ARENA work programme is split in one of the stopping places towards nal transparency of the earth atmosphere five networking activities dedicated to: Concordia. in the far infrared and in the submillimetre- • Management (including public outreach wave range was another strong incentive to actions) (NA1), raise the interest of astrophysicists. • Site assessment and provision of an access to a dedicated database (NA2), The primary role of the roadmap is to • Instrumentation in polar environment provide a comprehensive and consistent (NA3), plan for the development of an optimised • Logistics (NA4), research infrastructure for European as- • Astrophysical science cases (NA5). tronomy in Antarctica in the mid range Each of these activities are supervising (2010-2020) and to envision even more a number of tasks (see Table 1). ambitious project(s) beyond 2020, if An- tarctic astronomy turns out to be viable ARENA organized 11 dedicated workshops on the basis of the first results obtained and 3 plenary conferences (see Table 2) to These stations allow atmospheric cha- with the “pathfinder generation”. The foster close contact between researchers, racterization from the near UV to the roadmap aims at defining a number of engineers, industrial companies and di- submillimetre-wave range all year long. scientific milestones and goals that can rectors of polar institutes. This permanent Since 2005, date of the first wintering at be reached as well as the facilities that contact was essential to construct this Concordia, the various site testing ins- are required to reach them. ARENA was roadmap. The proceedings of the confer- truments are maintained during succes- not set up to “do science”, nor was it a po- ences are published by “Les Editions de sive winterovers. The ground layer which litical tool supervised by agencies such as Physique (EDP)” in its EAS Series (volumes concentrates the essential of the turbu- ASTRONET. It was basically a bottom up 25, 33, 40). Other more informal meetings lence is now becoming precisely cha- approach aimed at identifying the most were organized in parallel by the working racterized thanks to the accumulation of compelling science programmes that groups. The presentation made at these such measurements. can be proposed in the Antarctic condi- workshops are available at the ARENA tions, to evaluate the polar and logistics website. The website (http://arena.unice. In the frame of this race to the high pla- constraints on instrumental devices and fr) was opened at the University of Nice teau, the European network ARENA be- their feasibility in polar conditions and to provide the necessary information and gins its activities in 2006. It brings together to set up a comprehensive synthesis of news of the consortium. To complement the European and Australian astronomers the atmospheric conditions based on the ARENA web portal, a special site de- in order to define the basis of a future in- statistically significant sets of data. The dicated to the public outreach was set ternational observatory at Dome C, and ARENA work programme was defined by up and is maintained at the University of at the end of 2009 it proposes the present the end of 2005 and as it necessarily hap- Liège (http://www.arena.ulg.ac.be) (see roadmap. Besides, Chinese and Japanese pens in a rapidly evolving discipline, the Chapter 6). Each networking activity was teams are seeking to develop astronomy, management committee (Consortium subdivided into tasks chaired by expert at Dome A and Dome F, respectively. . Management Committee) and coordina- leaders belonging to various partner’s la- 19 20 Approach and scope

• • • • • • • • • • • .

Commission (see Commission European the to deliverablesdue 28 the were Theirleaders chargein producing of ders. There are 22 such tasks (see Table lea- ). 1 NA the by coordinated and boratory ted considerably to the final 3 final the to considerably ted contribu- and workshops specific held independently, workedconsortium. They ARENA the to belonging necessarily not community, industrial or academic the associatesfrom or designatemembers to responsability the given2007,were these per chair October werein appointedWG co- one and chair vision.One term long a with together (2010-2020) decade next the for projects instrumental appropriate of plan a and areas astrophysical mising Potsdampromost - 6 document to (2007) were established at the 2 werethe establishedat of the ARENACMC, (WG) workinggroups approval 6 the and 2007. mandate the in With began roadmap the veloping de- of task website.The the at available are documents these Officer. All Project the by approved eventually were They Period (2010) 1, report final 2,the and 3) (Reporting reports scientific annual rim inte- 3 the to attached were and agenda pre-established a to according produced pared for the 3 the for pared pre- was one second a 2008,then cember De- in CMC the to presented was version first iterations,a three in made was ration tion of projects to be supported. The prepa- a reportshort and to make their own selec- to elaborate its own roadmap of WG in annex). Each WG was entrusted list Members’ (see 2009 in Conference eeat ra wo ee independent were who areas relevant the in researchers leading to distributed roadmap.this of was version second The version is basically the matter of final the and EDP, 2010,tein, vol. 40) EAS Epch- & (Spinoglio Frascati2009 in May in A workedHow AREN 6 working groups Which astrophysics at DomeC? Logistics andoperations for instruments Antarctica (NA3) Toward large astronomical Site qualityassessment(NA2) Action (including public outreach) (NA1) Management oftheCoordination 5 Networking Activities Solar astrophysics Cosmic Microwave Background observations photometric Long time-series Optical/IR interferometry Submillimetre-wave (THz)astronomy Wide-field optical/IRastronomy A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) rd ARENA Conference held held Conference ARENA

Chapter 2).Chapter Theywere

Conference in in Conference (NA4) by preparing Chapter 4 rd ARENA (NA5)

Conferences andworkshops overallpolicy discipline.the of the of One European as an up set as to suchASTRONET ERA-NET well as - committees tion international) agencies - and their evalua - Moreover, it is the role of the national (and projects.solar or CMB instance kings,for ran- relativeprovide to body appropriate the not was ARENA that and astronomy of areas different very with deal they that groups,working recognizing different the by proposed projects the of ranking any was not unanimous - decided not to make this although - CMC ARENA The ported. sup- be to projects of selection own their conference.made this WGs The at made reflections and comments the account into takes reports the WG of The conference. version final the of session each of end the at held tables round various the roadmap,posed in participated wellas as pro- the on feedback and comments ded kersatFrascati the conference who provi - spea- invited also wereARENA. of These Tasks andsubtasks R eports forthcoming decade.forthcoming the in least atmaterialized be to chance a have will agencies polar the by vided bilities – possibly slightly improved – pro- that will match the present logistics capa- community, their technical feasibility and international wide a by support biguous ve their scientific excellence, their unam- to completion. Only those which will pro- waythe all out carried and funded be ly projects herewith proposed will eventual- the of fraction a only that clear is tics,it For obvious reasons of funding and logis- the European ScienceFoundation (ESF). “peer-reviewed” by be will Antarctica in Astronomy European of concept overall (see organizations these to recommendations their conclusions in the shape of a suite of submit to and supports the WG that jects cument as thoroughly as possible the pro - do- to basically was ARENA of outcome ). It is also likely that the the that likely also is 8).It Chapter Deliverables R oadmap and international agencies National .

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Table 1 List of ARENA tasks

Task Title Task leader(s) NA1 management of the coordination action Coordinator : Nicolas Epchtein (CNRS - Fizeau, Nice, France) 1.1 Contractual management Marie-Laure Péronne (CNRS - Fizeau, Nice, France) 1.2 Scientific management CMC members (cf. annexes) 1.3 Information, communication and public outreach Cyrille Baudouin and Marie-Laure Péronne (CNRS - Fizeau, Nice, France), Anna Pospiezsalska- Surdej (Université de Liège) 1.4 Technical management NA leaders

NA2 site quality assessment NA leader : Roland Gredel (MPIA, Heidelberg, Germany) 2.1 Parameters review Jean Vernin (CNRS - Fizeau, Nice, France) 2.2 Synthesis of observations at Dome C Roland Gredel (MPIA, Heidelberg, Germany), Aziz Ziad (CNRS - Fizeau, Nice, France) 2.3 Modelling the site properties for science optimisation idem

NA3 toward large astronomical NA leader : Jean-Pierre Swings instruments for antarctica (Université de Liège, Belgium) 3.1 Low emissivity optical configurations for infrared and Carlos Eiroa (UAM, Madrid, Spain) high dynamical imaging for Antarctic conditions 3.2 Telescope and instrumentation robotization Klaus Strassmeier (AIP, Potsdam, Germany) 3.3 Focal instrumentation for Antarctic telescopes Jean-Pierre Maillard (CNRS - IAP, Paris, France) 3.4 The International Robotic Antarctic Infrared Telescope (IRAIT) Gino Tosti (Università degli Studi di Perugia, Italy) 3.5 The IRAIT focal instrumentation Oscar Straniero (INAF, Teramo, Italy)

NA4 logistics and operations at dome c NA leader : Maurizio Candidi (INAF, Rome, Italy) 4.1 Logistics for the transportation of large astronomical instruments Patrice Godon (IPEV, Brest, France), and implication for construction of astronomical equipments Antonio Cucinotta (PNRA, Rome, Italy) 4.2 Logistics for the construction of large buildings and enclosures idem for telescopes at Dome C 4.3 Consumable needs and requests to the operators; power supply, Alain Pierre (IPEV, Brest, France), fluids and communications Chiara Montanari (PNRA, Rome, Italy) 4.4 Human questions - Training of polar teams Claude Bachelard (IPEV, Brest, France) 4.5 Environmental considerations Yves Frénot (IPEV, Brest, France), Sandro Torcini (PNRA, Rome, Italy) 4.6 Telecommunications Dominique Fleury (IPEV, Brest, France), Marco Maggiore (PNRA, Rome, Italy)

NA5 which astrophysics at dome c? NA leader : Hans Zinnecker (AIP, Potsdam, Germany) 5.1 Wide-field imaging surveys in the thermal infrared Maurizio Busso (Università degli Studi di Perugia, Italy), Mark McCaughrean (University of Exeter, United Kingdom) 5.2 New windows in the far infrared Pierre-Olivier Lagage (CEA/IRFU, Saclay, France) 5.3 Time variability: new domains for ground based high precision Heike Rauer (DLR, Berlin, Germany) and long duration time-series photometry and spectroscopy 5.3.1 Asteroseismology and helioseismology Eric Fossat (CNRS - Fizeau, Nice, France) 5.3.2 Photometric search for extrasolar planets Hans Deeg (IAC, Tenerife, Spain) 5.3.3 Solar-stellar connection Klaus Strassmeier (AIP, Potsdam, Germany) 5.4 Obtaining the ultimate angular resolution Farrokh Vakili (CNRS - Fizeau/OCA, Nice, France) 5.5 Spectroscopy and spectro-imagery Carlos Abia (Universidad de Granada, Spain)

21 22 Approach and scope . Poster ofthe1

Type

Table 2 3 2009 2008 2 2007 1 CONFERENCE CONFERENCE CONFERENCE

Workshop Workshop Workshop Workshop Workshop Workshop Workshop Workshop Workshop Workshop Workshop 2006 A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) rd nd st ARENA ARENA ARENA

A meetings AREN st ARENAConference for AntarcticOptical/IRAstronomy (Antarctica) forthenextdecade at CONCORDIA,prospectsandconstraints Large AstronomicalInfrastructures Progress onsitetesting 2 Interferometry Time-series observations from DomeC Spectroscopy Wide-field telescopes (in collaboration withOPTICONJRA4) Submillimetre astronomy at DomeC Site testingat DomeC Telescope robotization andinstrument at DomeC Visit toIRAIT Wide-field imaging at DomeC 1 Interferometry An astronomicalObservatoryatCONCORDIA Title The AstrophysicalScienceCasesatDomeC 1 2 Poster ofthe2 nd ARENAConference 3

December 10 October 13-14 September 17-19 April 16-18 26-27 March June 11-13 26-28 March September 12-13 June 14-17 May 10-12 September 17-21 October 16-19 May 11-15 June 25-27

Date Nice, France Garching-bei-München, Germany Catania, Italy Granada, Spain Exeter, United Kingdom Rome, Italy Santiago,Puerto Tenerife, Spain Perugia, Italy Paris, France Nice, France

Potsdam, Germany Roscoff, France Frascati, Italy Saclay, France Venue 2009

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

The Concordiastro towers

2nd ARENA Conference attendance in Potsdam Poster of the 3rd ARENA Conference

23 ARENA deliverables

24 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

2 ARENA deliverables

The ARENA network ARENA was committed to prepare periodi- annexed to the 4 annual scientific reports cally a set of contractual deliverables consis- (RP) to the European Commission. The members have delivered ting of reports on instrumental studies, tools present roadmap document constitutes the and data base providing access to site as- final deliverable. The following tables (see about 30 documents, sessments, and publication of proceedings Table 3 to Table 6) summarize the titles of from technical concept of conferences or summaries of workshops these deliverables and the main contrac- accessible through a web interface. These tors involved in their preparation. All studies to conference deliverables were prepared under the su- these documents are accessible through pervision of the networking activity leaders the ARENA website (http://arena.unice.fr) proceedings. with contributions of the task leaders and upon request to the coordinator. These documents were prepared by more than Table 3 List of deliverables (2006, reporting period 1) 100 experts from 8 countries with the aim Activity Deliverable Workpackage Delivered by Issued NA No Name Task No Contractor(s) in months of documenting in depth NA2 D2.1 Atmospheric turbulence 2.1 CNRS 6 the project of an parameters review NA3 D3.5 Six month reports on the IRAIT 3.4/ 3.5 CNRS 6 astronomical observatory activity at Dome C at the Concordia station. NA5 D5.4 Presentations of the workshops (2006) (ARENA website/CD Rom)

Table 4 List of deliverables (2007, reporting period 2)

Activity Deliverable Workpackage Delivered by Issued NA No Name Task No Contractor(s) in months NA2 D2.2 Analysis and archiving of Dome C 2.2 CNRS 12 site testing data NA2 D2.3 Update of site parameters in regards 2.1 MPIA 24 of science goals NA2 D2.4 Analysis and archiving of 1st Winter 2.3 CNRS 24 campaign data NA2 D2.5 Implication of relevant parameters 2.3 CNRS 24 D3.2 on science goals, ground-based instruments and site infrastructures NA3 D3.4 Proceedings of the workshop 3.3 CNRS 24 on focal instrumentation NA3 D3.5 Six months report on the IRAIT 3.4/3.5 INAF/UNIPG activity at Dome C 18 NA3 D3.5 Six months report on the IRAIT 3.4/3.5 INAF/UNIPG activity at Dome C 24 NA5 D5.2 Published Proceedings All tasks CNRS/INAF 18 of Conference 1 NA2 D5.4 Presentations of the workshops (2007) All tasks All 24 NA3 (ARENA website/CD Rom) 25 .A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020)

Table 5 List of deliverables (2008, reporting period 3)

Activity Deliverable Workpackage Delivered by Issued NA No Name Task No Contractor(s) in months NA2 D2.6 Analysis and archiving of 2nd Winter 2.2 CNRS/INAF/ 36 campaign data MPIA NA2 D2.7 Update of the implication of relevant 2.2 CNRS/INAF/ 36 parameters on science goals, MPIA ground-based instruments and site infrastructures NA3 D3.1 A report on the general constraints 3.1 CNRS 36 linked to polar conditions on optical configuration and particularly on adaptative optics NA3 D3.4 Report on the workshops on wide-field 3.3 CNRS/UGR 36 telescope and focal instrumentation (Exeter, Granada) NA3 D3.5 Six month report on IRAIT and AMICA 3.4/3.5 UNIPG/ 36 activity at Dome C INAF NA5 D5.2 Published Proceedings of Conference 2 All tasks AIP/DLR /CNRS 33 NA5 D5.4 Presentations of the workshops (2008) All tasks All 36 (ARENA website/CD Rom)

Table 6 List of deliverables (2009, reporting period 4)

Activity Deliverable Workpackage Delivered by Issued NA No Name Task No Contractor(s) in months NA2 D2.8 Book synthesizing the site qualification 2.1, 2.2, 2.3 CNRS/MPIA 43 With conclusions on the opportunities NA2 D2.9 Annual workshop on progress of the CNRS/MPIA 43 abc site testing (workshop presentations) NA3 D3.2 General guidelines on the design 3.1 42 of large IR (adaptive) optics NA4 D4.1 Report on the logistics of Dome C 4.1 IPEV/PNRA 42 for large astronomical infrastructures NA4 D4.2 Report on the construction of large 4.2 IPEV/PNRA 42 buildings for astronomy at Dome C NA4 D4.3 Report on consumables requirements 4.3 IPEV/PNRA 42 for large astronomical infrastructures and proposed solutions NA4 D4.4 Medical and psychological 4.4 IPEV/PNRA 42 recommendations for astronomical activities at Dome C NA4 D4.5 Report on impact study 4.5 IPEV/PNRA 42 on the environment NA4 D4.6 Report on telecommunications 4.6 IPEV/PNRA 42 NA5 D5.3 Published proceedings of Conference 3 All tasks INAF/CNRS 46 NA5 D5.5 Roadmap (this book) and executive All tasks All 46 summary of recommendations to the national and international agencies (ESO-ESA) for an astrophysical programme at Dome C ARENA deliverables

26 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

27 28 Site quality assessment

SBM ASTEP 400

ASTEP SUD

PAIX GSM DIMM MOSP LUCAS Site-testing A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020). instruments at Dome C

3 Site quality assessment 3a Available data

Site qualification he release of site testing data to the year, compared to only 30% of the time on community via an electronically ac- the Llano Chajnantor. The measurements is a prerequisite for cessible data bank was one of the and model calculations indicate that Tmain objectives of the ARENA contract. Dome C is probably the best site known proceeding with future, Their access is now available via the ARENA on Earth for submillimetre astronomy. expensive astronomical website (http://arena.unice.fr). The database includes the seeing and isoplanatic angle A low atmospheric water vapour content developments in data taken during the summer and winter results in higher transmission in the near- campaigns starting in December 2004, to mid-infrared windows and an exten- Antarctica. Measurement and the meteo-balloon data taken during ded wavelength coverage. The highest and assessment the 2001-2004 period in the framework benefits for observations in the thermal of the Concordiastro1 programme. The infrared regime arise from the very low of relevant atmospheric site provides a link to the AASTINO data- temperatures at Dome C, as discussed in base as well. Data taken during the PNRA the following section. parameters already campaigns are available via the web-ac- gathered must be cessible database at www.climantartide.it. Sky brightness at infrared wavelengths archived, calibrated Precipitable water vapour (PWV) At wavelengths above 2.3µm, the domi- and put at the disposal Measurements of the precipitable water nant parameter that determines the bri- vapour (PWV) have been carried out ghtness of the sky during day- and night of scientists and decision during the last decade and relatively ro- time is the temperature of the atmos- bust statements are possible as far as the phere. In the thermal infrared, most of the makers. A major task absolute values are concerned. Monthly observing programmes are background + averages range from 0.72(- 0.20)mm in limited, and the integration time needed of ARENA was + December to 0.26 (- 0.1)mm during the to reach a given signal to noise ratio is to synthesize these data, March/April period. Variations in the PWV proportional to the sky background. by factors of 2-3 occur on a daily basis. provide easy access A systematic monitoring of the short- Data obtained at the South Pole demons- to them through Internet term variations in PWV is in progress at trate that compared to the mid-latitude the COCHISE submillimetre telescope. observatories, the sky is darker by factors databases and to identify The 200µm bolometer camera CAMISTIC of 10-100. Daytime measurements of the from CEA/Saclay, to be deployed at the infrared sky brightness at Dome C were the as yet undocumented second Nasmyth focus of IRAIT, will even- obtained during the two summer seasons parameters for future tually sample small spatial fluctuations in 2003 and 2004. in the atmospheric emission that arise investigations. from small water clouds in the lower at- Sky brightness measurements in the 2-28µm mosphere, thus allowing to determine the wavelength region will eventually be ob- stability of the sky noise at this frequency. tained with the AMICA camera on IRAIT,

Measurements demonstrate that the 200µm 1Concordiastro is a scientific programme window opens at a transmission level carried out by LUAN Laboratory (Université about 20% during 25% of the time. De- de Nice Sophia Antipolis), with contributions tailed atmospheric transmission models of Observatoire de la Côte d’Azur (OCA) (e.g., MOLIERE) have then been used to and Osservatorio di Capodimonte at Napoli estimate the PWV and show that observa- (OAC), and funded by the polar institutes tions at 350µm and 450µm are possible all IPEV (France) and PNRA (Italy).

29 30 Site quality assessment . accessible from theground. spectral windowsto access not otherwise significantvery cost savings, as well as the ge, deep mid-IR surveys, and consequently savings in the time needed to carry out lar Pole. Dome C thus offers very considerable pected that Dome C is as dark as the South temperatures,givensimilar but the ex- is it ult ta cn e ece i optical and near-infrared imaging altogether. in reached be can that quality enclosure, likelyand very limit the image its and telescope optical an of ronment envi- thermal the of control the to blem temperature variations pose a severe pro- reported. havebeen minuteslarge of The in the winter exceeding 10°C in the matter summer.in 10°C/hour Temperature jumps gradientsthat exceed diurnal > and dT/dt winter,the during week per 30°C to up of values large very the reaches oscillation months.The winter and summer during si-periodic ground temperature oscillation the PNRA programmes demonstrate from a qua- obtained data meteorological The Temperature andwindprofiles tion over DomeC. extinc- visual of magnitude the evaluate to needed are measurements extinction which is poor by all standards. Continued the V-band,in airmass per mag 0.5 to up PAIXextinction visual ratherhigh showa from obtained winter.results Firstthe in 80-85% of order the of is and camera sky C has been fromdetermined the Gattini all- Dome at nights clear of fraction The of -18°, which is1,767hours. elevation an below is sun the where mit li- the from obtained is what than larger of dark hours per year is thus significantly C.numberDome This for year per hours tions of -12° results in a total of 2,506 dark The fact that the sky is dark at solar eleva- until the sun is below an elevation of -18°. background sky the dominates aerosols by scattering multiple sites,where titude mid-la- from different clearly is C Dome already.-12° at of situation elevation The solar a atdark is sky the thatshowsmera ca- GattiniSBC the with measured length wave- optical the in brightness sky The Optical clearnights,of A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020)

sky

brightness, andvisualextinction

fraction

(GSM) seeing monitor Generalized from satellites hasbeengiven. obtained datameteorological of analysis variation between summer and winter. An show any strong diurnal variations, not apart from do a profiles speed wind layer wind speeds are very low indeed. Ground observations,vorableastronomical for as - fa very are C Dome at conditions Wind pends ontheouterscaleaswell. Fortelescopes,larger de- quality image the for the technical specification and the and specification technical the for parameter important an is scale outer The Outer scaleL outer scales in the range of L medium-size, 2-4mclass telescopesandfor trivial.not For is telescope optical an with reached be can that quality image the of terms in data DIMM of interpretation The for heightsof20m above theice. above8m and 3m ice,the around40min and of elevations for 30min around are 0.”5,than better seeing events,for seeing good the of duration mean the DIMMs, indeed good 0.”36.of three order the From very the of and is layer the boundary above seeing atmosphere free The height of23minwinter. mean a with layer boundary turbulent a by caused are values summer. poor The at 8m height is 1.”65 in winter and 0.”57 in 2”measured median.seeing median The worsethan mediocreatand is seeing 3m the that show 3m,height at 8m,20m and placed DIMMs three with obtained Data telescope. anoptical of production tific tal parameter which determines the scien- obtained.fundamen- a thus is seeing The being is that quality image final the with to noise ratio S/N scales roughly inversely For seeing-limited observations, the signal Seeing oa dgaain eul te seeing the equals degradations local of absence the in obtained quality image Table 7 are limited to the period fromare limitedtotheperiod July toOctober2005. 955). 499,The seeingisgiven inarcsec atl A&A al. et (Aristidi half (Dec. data 2004 to DIMM April 2008) available except for three the P75DIMM and P25installed the are the 75%at and an25% for percentiles.elevation of statistics 20m forThe datawhich seeing have beendata collected Global during 3 years and Min Max P P Median Mean Elevation 25 75 e 0

DIMM summer 0 0.03 4.76 0.70 1.32 0.95 1.06

data winter 0.24 9.26 1.86 2.98 2.37 2.51 3 m 0 = 20-30m, the total 0.03 9.78 1.06 2.38 1.67 1.83 e 0

. summer ters. L thatindicationsThereare interferome - baseline long and lescopes 250-400m during high-summer.250-400m during layer, boundary reaching the up to an elevation of of about height the in variation day-time regular a revealed 1999-2000 of summer the during obtained results The seeing above layer theboundary is0.”36. ght of 23m, and that the free atmospheric a sharp upper atboundary a median hei- ginates some 2m above the ice, that it has statistical average, the boundary layer - ori From those data, it is concluded that on a latitude sites range from L from range sites latitude of L of values small (GSM), very monitor seeing generalized the with campaign a Using systemsaswell.metric trackersinterfero- for fringe of design the eecp daees > L > D diameters telescope For (HAR). techniques an- resolution gular high of optimisation performance poral andvertical variation in tem- the infer to 2006 of winter the ring du- flights balloon 35 some with gether to- threeDIMMs Datafromthe obtained layerBoundary and L of measurements obvious. Further not is towera locatedon facility a valuesfor se 3.5m above the ice, of and the significance height of the- a at located instrument was campaign out carried from the ground, with the GSM The variations. diurnal L of deformable mirrors depends on L on depends mirrors deformable of to correct for need the minimizing thus largely reduced, are modes aberrations Zernike aito of variation systems depends critically on the vertical MCAO and GLAO of well,design the and low values of L 0 0 0.03 7.63 0.40 0.86 0.57 0.69 willbeobtainedwithMOSP. (h). The outer scale has implications for 0 <10m were measured.were <10m Valuesmid- at e.g. winter 0.13 9.09 0.83 2.32 1.65 1.72 8 m C , tip/tilt. The required stroke 0 n 2 are beneficial for large te- (h) and the outer scale scale outer the and 15.05 C total 0.03 0.52 1.69 0.98 1.23 n 2 (h) 0 = 20-30m.= The profiles 0 te lowest the , C =0.5µm. 0 exhibits n 2 20 m 8.20 0.13 0.43 1.55 0.84 1.10 (h) . 0 as as

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

The absence of significant turbulence coherence times superior to 10ms. These above the boundary layer results in a very characteristics raise the possibility to im- low scintillation and offers improvements plement a solar observatory with excep- by factors of a few in the photometric tional capabilities of high angular resolu- accuracy that can be reached from the tion over extended periods of time. ground. The photometric ICE-T Explorer The SODAR Telescope is designed to take full advan- instruments But not only: low water vapour content measures tage of the improved photometric condi- makes the site particularly suited for IR, the wind speed tions, and once installed will obtain uni- height profile millimetre and submillimetre observations. que time-series observations of a single that determines Dome C should display IR sensitivity gains field during an entire polar night. the atmospheric relative to the South Pole, already one of turbulence. the best sites on Earth, of up to a factor of 2 Our present knowledge of Cn(h) is based 2, while in the mid- to far-infrared the gain on a rather limited amount of data. The over South Pole raises to a factor 100, and methods that have been employed suffer up to 3 orders of magnitude compared to from a relatively low vertical resolution, AASTINO the best mid-latitude sites. and, in the case of the balloon flights, from is an australian a very limited temporal coverage. The pre- autonomous Finally, meteorological studies and anec- vious SODAR measurements obtained in station that dotal evidence point to a low sky bri- the framework of the STABLEDC and AAS- measured various ghtness, suitable for coronal observations. TINO campaigns have a vertical resolution atmospheric Preliminary analysis of data from an of 13m. In the future, a better temporal sam- parameters ongoing systematic study on the sky bri- pling of the boundary layer will become above Dome C. ghtness during summer months indicate a available from the SONICS experiment, sky brightness at least better (lower) than which now runs six sonic anemometers in the best mid-latitude sites by a factor 2. on the extended 45m high meteo-mast. In summary, these peculiarities could permit The SONICS From SODAR data obtained within the a versatile observing facility, with capabili- measure TMT site testing campaign, it becomes the turbulence ties in many respects intermediate between clear that a very strong contribution to at different a ground and space observatory, especially the total seeing at potential astronomi- heights above if taking advantage of the small size of the cal sites in Chile, such as Tolonchar and the ice (7, 17, 22 Turbulent Ground Layer (TGL) (instruments/ Cerro Armazones, occurs below heights and 30m). telescopes on a 30m tower). . of 40m and 60m, respectively, and that the seeing on Armazones, Tolonchar, strong high-altitude winds in winter, which Mauna Kea, and San Pedro Martir above introduce some high-altitude turbulence. a height of 60m ranges from 0.”4 to 0.”6. The isoplanatic angle carries a h5/3 term The UNSW has developed and tested a which leads to a higher influence of tur- SODAR which provides vertical and tem- bulence from high altitudes. poral resolutions of 1m and 1s, respectively. SODAR data obtained at Dome A A very limited number of balloon flights show that variations in the height of the were used to obtain the coherence time t0. boundary layer by factors of a few occur In general, the coherence times are very on short timescales. Measurements on large and of the order of 5-11ms, caused Dome C with high resolution optical by the absence of strong turbulence at profilers are urgently needed in order high altitudes, yet significantly smaller va- to fully characterize the temporal and lues have been reported elsewhere. These 2 vertical variations of Cn(t, h). Calibration findings confirm the need of continued 2 between optical profilers and other tech- and detailed measurements of Cn(t, h), niques (SODAR, SONICS) is necessary for together with meteo-balloon flights in site comparisons. summer and in winter to acquire accurate wind profiles v(h,t).

Coherence time t0 and the isoplanatic angle q0 Additional note concerning The efficiency of adaptive optics and day-time observation conditions high angular resolution (HAR) techni- On average, day-time seeing at Dome C ques depends on the coherence time t0 is better than in the best other sites on and the isoplanatic angle q0 . For Dome Earth – even accounting for the relatively C, a median value of q0 = 3.”9 is inferred, low elevation of the Sun, e.g., Sac Peak with values as large as 7” during summer. (1.”16) or Fuxian Lake (1.”2). And — of During winter, relatively low values of q0 importance for high resolution and inter- have been measured, similar to values ob- ferometry — the isoplanatic angle also tained at moderate, mid-latitude sites, and appears to be significantly better, up to The DIMM the South Pole, where q0 = 3.”2 is estimated 7”, compared to ~3” at South Pole and on the from in-situ radio soundings. The small va- even smaller at mid-latitude sites. Other ConcordiaAstro lues are probably due to the occurrence of measurements also point to exceptional plateform 31 32 Site quality assessment D 3b at DomeC at characterization to thesite finalize . flights have been used to infer used been have flights lers as such as SCIDAR, MASS, and balloon urgently needed. thus are resolution temporal and spatial better a provide which solution.Profiles re- temporal and spatial low very at yet riations in riations knowledge of the temporal and spatial va- detailed a requires systems of these of tion use make will systems.optimiza- GLAO The and MCAO C Dome at deployed telescopes that expected be to is It C the telescopeandtower design. constrain and specify to assistance of be SL.the on simulationsThenumerical will interactions these of impact evaluatethe the SL-telescope-tower interactions and to Detailed models are needed to investigate rov turbulent cascadeat larger scales. Kolmogo- the breaks flow incoming the with tower and enclosure telescope the of interaction the whether clear not is It the Interaction between near- tomid-infrared observations. and optical of degradation potential the evaluate to needed are SL the of models scales. spatialand measurements Detailed and temporal small on vary is to layerexpected surface the A, Dome at rements measu- from turbulence.evidenced tal As (SL) which contributes layersome 95% of the to- surface a by dominated is C Dome of Modeling high vertical resolution A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) n 2 (h) the telescope and structure profile with turbulence surface layer rements remain tobeperfomed. measu- C,of numberDome fora ble espite the large quantity of data availa-

What is needed isneeded What C

n 2 (t,h) and L and

the SLand 0 .profi- Different towers C n 2

(t,h)

be deployed at DomeC. to interferometers future of specification directmeasurements are required for the from estimations these of Confirmation coverage. sky of terms in cophasing ter interferome- the relaxes at which Paranal, than larger times three than more is C data.Dome atGSM angle isopistonic The tonic angle have been obtained using the isopis- the of estimatesModel-dependent direction ofthetwo sources. the in same the specifications, is within certain piston, atmospheric differential as source,science the domain which thatmeans the isopistonic same the in ted known.loca- be be to should source The needs source reference a using lescopes ferometer, the co-phase of the different te- inter long-baseline multi-aperture a with magnitude limiting suitable a reach To Measurement moderate resolution, aswell. atmospheric windows should be made at IR the of opacity spectral the of nitoring mo- stability. Accurate and transmission atmospheric submillimetre-wave the of Monitoring infrared). the summer, in in (and winter in 40µm to visible the from and Monitoring of of comprehension a techniques, and HAR specification and the optimization of the the for parameter crucial a is time rence data.balloon of number cohe- cient The statisticallyinsuffi- a from were obtained The available data on the coherence time for HAR Coherence of q the isopistonic angle 0 isrequired. thermal emissionof techniques time measurement

the

transmission

. the sky

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

33 34 Astrophysics at Dome C Tarantula Nebula A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

4 Astrophysics at Dome C

Major astrophysical The prerequisite for the development of major astronomical facilities in Antarc- questions, ranging tica is to demonstrate that as a result of the exceptional polar atmospheric from the characterization environment one would gain orders of of exoplanets magnitude of improvement on essential parameters such as overall sensitivity, an- to the polarization gular resolution, or duty cycle.

of the CMB, could greatly In a single sentence, these new facilities benefit from observations must provide essential data to solve major astrophysical problems that could not be carried out in the obtained from any other place on Earth or, at an unrealistic cost, from space. A ma- Antarctic environment. jor activity and concern of ARENA mem- ARENA has set up bers and, in particular NA5, was to identify these “scientific niches” and to propose six working groups instrumental concepts able to achieve to investigate, in their them. To this purpose, six specialist working groups (see Chapter 1c) were set up fields of expertise, to investigate their top-level science cases and requirements. These working groups the most promising produced reports that constitute the body astrophysical of the present chapter. . breakthroughs and to carry out preliminary concept studies of the appropriate instruments-including their logistics impact and financial requirements. The Butterly Nebula (composite of three exposures through broad-band blue, green and red filters, lasting a total of 25 minutes at the ESO VLT)

35 36 Astrophysics at Dome C . emphasis. discussions its conducted WG1 in differ conclusions final the although WG1, of deliberations the influenced gly Theresults PILOTthe of study have stron - Antarctica. in telescope optical/IR 2m- class a operating and building of issues cases,science ral technical the wellas as seve- of examination in-depth an volved in- study 2008.design Thisin completed study undertaken for the PILOT telescope, design preliminary the closely followed also 2007.PotsdamIt in and 2006 in coff Ros- in held conferences science the lar - particu in meetings, ARENA–sponsored various the at made presentations many WG1 was informed of the discussions and so. that do to order in The with dealt issues be must principal the with together red telescope that might be built at Dome science C,drivers for a 2m-class optical/infra- the considering of brief the with formed The ARENA Workingwas (WG1) 1 Group Working group activities 4a and infrared astronomy A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020)

Wide-field optical

3 2008, the December at report final its and report atnary the Paris ARENA meeting in largely electronically, presenting a prelimi- extended source imaging in the thermal- the in imaging source extended for site temperate good a on telescope 8m-sized an of equivalent the Antarctica for thus, in instance,telescope telescope,2m-sized a making and sky both from the background reduces cold flow. The air stable its planet,and our on location plateau,high coldest,Antarctic the driest environment the the knowledgeof of the was this Motivating C. Dome at located single,a using studied 2m-class be telescope might the it as consider spectrum, IR to and optical was WG1 of task The lengths,particlespectrum.acrossthe and for astronomy, from optical to radio wave - opportunities excitingscience of range a clearis It that the Antarcticplateau offers Science andcontext rd rd ARENA Conference inMay 2009.

most feasible path forward for the first first the for forward path feasible most infraredprovide the for prospectsthe and opportunities B).that concluded TheWG ground (about 10-20m to be studied the during a phase to closer much telescope a from data sharper secure to GLAOdevice infraredthatmeans we make can a of use facility.optimised Moreover, an infrared- the movingto for than greater significantly are telescope optical an of construction this requirement places on constraints the design and the that apparent became it work its continued WG the telescope, as Antarctic an fordesirablefeature a mains imaging,mited was high. li- reWhilestill - this near-diffraction of capable optical telescope, an in interest layer. Hence dary ght be obtained above a ~30m high boun- mi- seeing optical superb that suggested recently had C Dome from results testing deliberations,its began the WhenWG site ble from temperate sites. obtaina- than optical the in quality ging and hence the possibility of superior ima- layer, inversion surface narrow a above plateau, Antarctic the over obtained be that propose to 1989 “super-seeing” might in Gillingham led Peter first had flow air the of earlier,stability mentioned the As other IR windows used throughat temperate sites. transmission the improving as wellviewing, regularas for mid-IR the in windows up open IR.conditions dry The A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

+ QN at 20µm and Q at 30µm). Above telescope is the next step in developing 3µm, observations can be carried out Antarctic optical/IR astronomy. It is ca- during daylight periods and moonlight is pable of delivering unique and exciting not a limitation. science for relatively modest cost, while also demonstrating the future possibili- The near-infrared performance gains of an ties for larger Antarctic plateau telesco- Antarctic telescope arise from the combi- pes (and possibly interferometers). nation of the relatively high spatial resolution and the low thermal background. Science cases Comparing against future telescopes, the A 2.5m diameter Dome C telescope could primary ELT role in the near-infrared will undertake a wide range of competitive be for high spectral and/or spatial resolu- science. However, the WG1 is conscious tion observation. JWST will be diffraction that due to the special conditions of Antarc- limited and 10-500 times faster than any tica and the numerous other challenging existing ground based telescope, as well instruments, only a selection of them will as ~20 times faster than an Antarctic 2.5m. appear in the final roadmap. Three key pro- Both ELTs and JWST are observatory-class grammes for such an infrared optimised fa- facilities, however, and neither is focussed cility are identified: (i) the distant universe, on wide-field science. A complementary including first light in the universe and the survey telescope is needed for the sur- equation of state of the universe, (ii) exo- veys discussed below, programmes that planet science and (iii) galactic ecology. an Antarctic 2.5m-class telescope would The order in which they appear and are be uniquely capable of undertaking. described below is not a priority ranking. These key programs in turn define two The mid-infrared wavelength range falls in initial instruments that will be required. A the large gaps between ground and space third one is also considered as a commis- telescopes in terms of survey speed, and sioning instrument. Other instruments are between large-aperture, small-field teles- also identified for Phase 2 operations. copes and small-aperture, wide-field telescopes in terms of resolution. An Antarctic Key programme 1: The Distant Universe telescope would be the only telescope ca- (Wide-field, near-infrared imager) pable of obtaining moderate spatial reso- 2m-class telescope for Antarctica. Such a lution photometry over very wide regions First light in the Universe telescope also provides a range of exciting of sky, and thus an ideal complement to This key programme aims to measure the science programmes that are competitive both the deep, narrow fields of JWST & signatures of the final evolutionary stages with those that may be conducted from ELTs and the wide area, low spatial reso- of the first stars to form in the Universe, and any other facility available to astronomers lution fields of Spitzer & WISE. the properties of the first galaxies. Pair-ins- today. The report of WG1 follows. tability Supernovae (PISNe) are predicted In the instrumental parameter space do- to be extremely powerful explosions that Dome C potential main, this working group identifies seve- occur in massive progenitor stars formed An optical/infrared telescope at Dome C ral characteristics that should be inclu- in low metallicity environments and would be supremely powerful for its size, ded in the design of an infrared telescope should thus be numerous amongst the enjoying not only a substantial advantage in Antarctica: first Population III stars. A 2.5m Antarctic in both sensitivity and photometric ac- • Wide-field is fundamental: the instanta- telescope should be capable of finding curacy over comparable ground-based neous field can be very large, up to ~ 1 PISNe out to a maximum redshift in the facilities, but also having a wide-field, hi- square degree. range z = 7-10, via a dedicated search in gh-resolution, high-cadence imaging ca- • High angular resolution (about 200 or the near-infrared. Together with JWST, pability otherwise achievable only from 300 milli-arcsec) is essential, especially these would be the only facilities capable space. This is a result of the improved bac- if combined with wide-field. Due to the of detecting such high-redshift objects, kground, transparency, stability and seeing stability of the atmosphere, high image qua- but each probes a different region of the conditions on the Antarctic plateau over lity can be homogeneously reached over PISNe parameter space. temperate latitude sites. New and impro- the complete field using a ground layer ved atmospheric windows are opened adaptive optics system and/or a tower. Because of their high intrinsic luminosity, thanks to the extremely dry air. Low turbu- • Time monitoring is important because gamma ray bursts (GRBs) offer a powerful lence results in the free-air seeing being long observing periods are available with probe of the Universe at a range of cos- more than twice as good. Longer obser- good, stable observing conditions. mological distances. The highest redshift ving times are available due to clearer • Spectroscopic capabilities should be GRB so far detected is at z = 6.3; theories skies and more stable backgrounds. included, in addition to those for conti- suggest that objects should be numerous nuum imaging. at even higher red-shifts in the range z = Taking the combination of these gains, the 10-20. While current high-energy satellites primary wavelength range identified by To be competitive, the working group be- find hundreds of GRBs per year, there is this working group for an Antarctic teles- lieves that such an Antarctic telescope a paucity of uniform optical/infrared af- cope is in the infrared. This includes both must be larger than 2m. Although the terglow observations. A 2.5m telescope the near-infrared (in particular, the bands science that could be attained with a 4m would be expected to find several z > 6 of Kdark at 2.4µm, L’ at 3.8µm and M at telescope or larger would simply be ex- GRBs per season and at least one z > 10 4.7µm) and the mid-infrared (N’ at 11.5µm, ceptional, we believe that a 2.5 diameter GRB after a few years of monitoring.

37 38 Astrophysics at Dome C . range canbeexplored. L the galaxies.In of 3, the peak for star bursts in the evolution to redshifts.2 = z for band K the in lies It all at formation star of tracers main the universe.Ha redshift The high- universe,the local to the used in today largely parameters, physical of the determination the extend to suited 5.< z < 2 perfectlybe will telescope This at galaxies for range optical rest-frame the to corresponds range 4µm to 2 The red, which ismuch betterthan WISE. mid-infra- the in diffraction-limited and infrared near the ~0.’’3 in of resolution spatial a JWST, at than and fields wider much on surveys imaging undertake to able instrument complementary perfect a is telescope 2.5m ment).Antarctic An in the 1 to 5μm domain - (NIRCAM instru only and (~2’x2’) fields size medium on but resolution, image incomparable an offer will JWST and resolution angular low range,at 23μm to 3.3 the in survey imaging all-sky an make to started just imaging.infrared deep WISE to devoted be will JWST and WISE like telescopes background.space Future thermal high ground- the by hampered are mid-latitude telescopes based infrared, the interest. In cosmological their by driven surveys, imaging extragalactic to voted SPITZER, AKARI…) are or have been de- HST, (ISO, space in and BARU, VLT…) ground the CFHT, DENIS, 2MASS, UKIRT, on (SDSS, SU- instruments and mes program world-wide- of number large A Deep infraredimaging surveys Australian Observatory), asdesignedforthePILOTPhaseA study. (Anglo McGrath Andrew of courtesy Image dome. calotte-style a inside and tower a of top on mounted C, Dome at like look might telescope IR 2.5m a how of image CAD 1 Fig. A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) ’ band the z = 4 to 5 to 4 = z the band line is one of one is line

K view would also allow a wide-area 2.4µm of field wide the and emission thermal universe.sky the low Theof history tion - forma star the of understanding an ving achie - to crucial are domains two These ghtness in this spectral domain,spectral this in a ghtness allowing have stars M and K the maximumtheir - bri remarkabledepth.a reach to Furthermore, plying these in the near infrared can enable Ap techniques.- micro-lensing and transit unique properties of Dome C. These are the rization of exoplanets can benefit from the Two techniques of detection and characte- and mid-infraredimagers) (Wide-field near-infrared Key programme2:ExoplanetScience: derivedlogical parameters from them. improvedning cosmo- the constraintson curves,light interpretationSN of obtai- so Dome C should thus allow more accurate from reached be can whichdepth the at derived Hubble diagram. SNe in this band curve, light the in errors to leads which turn in optical the from brightness solute ab- and distance their of estimation the dusty,are in introduced are uncertainties these explode.If they which in ronment envi- the by constrained strongly is use probed.be Universecan the of tion Their accelera- cosmic whichthe with candles standard are SNe Ia evolution. Type lar stel- and evolutioncosmology, galaxy of intersection atthe are Supernovae(SNe) The EquationofStatetheUniverse with otherfacilities. possible than masses limiting lower at dark survey to find more distant galaxies distant more find to survey

transits from thesameground-based site. of types these both follow to possible it making of capability unique the offers C obtained.Dome be also can day-side planetary the of spectrum well, emission an as star) its secondary behind (planet the transit of measurement With s oiae b cmo molecules common such as H by dominated is emission range,the where5μm to 2 the transmission in planet.Observations the of the spectrum derive can one the star, off other the and transit) (primary star its of front in obtained one planet, the of spectra two between the difference From event. the during hundreds) (few resolution low at spectrum stellar the and recording by profiles, hazes) temperature clouds, (molecules, composition their through atmospheres, the planetary the characterize is to targets, way only brightest the by selecting transits, known of observation The Exoplanets by the transit technique ofcontinuous20-40 hours observations. These typically would require no more than to undertake observations only under alert. networks,severalglobal by conducted but exoplanets,being alreadyof are tection as de- of programme another commence to not is goalhere thatthe stressed mustbe It observations,series seeSection4d ). has also been given science priority by exoplanet WG 4 (Time- that note should One process.formation planet the of appraisal full a for necessary is census a stars.Such these around planets of study systematic 2 ,CH C O, 4 O C , 2 , are recommended.

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Table 8 Performance Characteristics of an Antarctic 2.5m Optical/IR Telescope

2 Expected resolution and sensitivity for an Band Priority l (m) R(l/dl) FWHM (arcsec) ma b ma b /arsec Prospective Instrument Antarctic 2.5m telescope. The resolution, G 2 0.47 3.4 0.35 27.6 27.1 Visible Camera, over the full imaging field of view for each 0.08’’ pixel scale, 40’x40’ FOV camera, is given as a function of wavelength, R 2 0.62 4.4 0.33 27.1 26.5 including tip-tilt to remove boundary-layer I 2 0.76 5.1 0.32 26.6 26.0 turbulence and tower wind-shake. For l > 3µm near-diffraction limited performance is Z 2 0.91 6.5 0.31 25.8 25.1 achieved. Point source and extended object Y 2 1.04 5.1 0.30 25.5 24.8 limiting sensitivities (in AB magnitudes) are also given for a 5s, 1hour integration, assu- J 0 1.21 4.6 0.30 25.0 24.3 Near-IR camera ming that the sky background is summed H 0 1.65 5.7 0.29 24.6 23.8 0.06’’ pixel, 4’ FOV over 4 times the FHWM disc (for point sources), 0.15’’ pixel, 10’ FOV the telescope is at 227K with 5% emissivity, Kdark 0 2.40 10 0.32 25.3 24.7 or more the overall optical efficiency is 50% (inclu- L 0 3.76 5.8 0.40 21.2 20.8 Near-IR camera ding throughput, detector efficiencies, and se- 0.15’’ pixel, 10’ FOV condary mirror obscuration). The proposed M 0 4,66 19 0.46 19.6 19.4 instruments are indicated in the final column, N’ 1 11.5 11 1.05 16.3 17.0 Mid-IR camera (blue arm) together with their pixel scales and fields of 0.8’’ pixel, 14’ FOV view. Columns 2 lists the priorities: in agree- QN 1 20.1 20 1.80 14.6 15.8 ment with the text, the NIR camera has the Q+ 1 30 20 2.7 13.4 15.1 (red arm) 1.3’’ pixel, 6’ FOV highest priority.

Exoplanets by the micro-lensing technique of magnitude better than achievable with for free-floating planets in nearby star for- The method is complementary to the tran- mapping surveys using millimetre-wave ming regions. sit technique, which is more sensitive to telescopes, and is nearly two orders of • Diffraction-limited imaging science: a planets within 1 AU of the star. It requires, magnitude better than the current best range of projects for high resolution first, a search for amplification events by southern Galactic plane molecular sur- imaging in the optical over small fields wide-field telescope networks pointed to- vey. It will enable the molecular medium (“Hubble from the ground”), including wards the Galactic Bulge (GB), to obtain to be viewed with a new clarity of vision. solar system science and emission line the highest probability of alignment of a A central issue relating to our understan- mapping of galaxy centres. star belonging to the disk to act as a lens for ding of the Galactic ecology is what the a source in the GB. The full crossing of the turbulent energy distribution is, and how Instrumental requirements Einstein circle can take up to 60 days, moni- it relates to the contrasting pictures of The baseline optical design comprises tored by specialized networks (e.g., OGLE local turbulence injection from the natal a 2.5m Ritchey-Chrétien telescope with and MOA). Then, the follow-up of the stron- stellar content or whether it arises from f/1.5 primary and f/10 overall focal ratios, gest light curves is undertaken by other external sources? Such questions can be giving diffraction-limited performance at telescopes organized in a network (e.g., addressed by unveiling the molecular 1μm over a 1° field. Instruments are moun- PLANET). For the best chance of detecting galaxy, mapping directly the distribution ted on twin Nasmyth foci. The telescope the perturbation of the light curve due to of its principal tracer, the hydrogen mole- is housed in a calotte-style dome at an a planet, continuous monitoring is neces- cule, on the arcsecond scale. altitude of about 10-20m (to be studied in sary during the ~two days around the light Phase B) (see Fig.1). The enclosure is tem- maximum. Photometry undertaken in the K Other science programmes perature and humidity controlled, protec- band, rather than in the visible, significantly There are many other frontline science ting the optical elements from large spatial reduces the extinction toward the GB. The programmes that such a 2.5m telescope and temporal thermal gradients, and pre- two Magellanic Clouds are also favourable in Antarctica could undertake. Some pos- venting frost formation on optical surfaces, targets for this programme. All these requi- sibilities are listed below: so allowing, with the use of a Ground rements are favoured by measurements • Dark energy and the evolution of struc- Layer Adaptive Optics and/or a tip-tilt sys- made from Antarctica. ture: observation of weak gravitationally- tem to reach the superb natural seeing lensed galaxies; and a study of a sample above the ground layer. The need for a Key programme 3: Galactic Ecology of moderate-redshift galaxy clusters. tower is to overcome the steep vertical (Wide-field, mid-infrared • Stellar properties and populations: a temperature gradient in the boundary spectroscopic line imager) near-infrared survey of disk galaxies in layer (up to 20°C in ~30m), as well as fros- This programme aims to investigate the the local group to study the processes of ting on exposed surfaces caused by the molecular phase of the Galaxy. An An- galaxy formation and evolution; a deep super-saturated water vapour in the inten- tarctic telescope should be able to map mid-infrared survey of the Large and sely cold air 2 (see also the next section). the mid-infrared emission from the pure Small Magellanic Clouds in order to un- rotational lines of H2 at 12 and 17µm in derstand star formation processes and the typical warm environment of mole- extreme populations of AGB stars. 2 It should be noted that there is minimal effect cular clouds at a spatial resolution of ~2’’ Star and planet formation: a series of • on telescope sensitivity caused by placing it over a wide region of the Galactic plane. mid-infrared spectrophotometric surveys on a tower rather than on the ice surface, even This could not be done from a tempe- searching for signatures of embedded pro- though this is a warmer environment, if the te- rate latitude site as a suitable telescope tostars, crystalline silicates, and circums- lescope has sufficiently low emissivity so that would not have sufficient sensitivity. This tellar disks around young stellar objects sky emission still dominates over telescope spatial resolution is more than an order and brown dwarfs. The infrared search thermal emission. 39 40 Astrophysics at Dome C . • • • sing from the low atmospheric thermal thermal atmospheric low the from sing long coherence time). the and angle layer,isoplanatic wide the seeing, turbulentboundary the of lowheight the atmospheric free from excellent (resulting the turbulence layer dary boun- residual the of correction GLAO) and/or (tip-tilt partial with near-infrared for thefollowing kindsofobservations: observatory latitude temperate a at cope perform a similar or somewhat larger teles- telescope are given in transfer CCDs. orthogonal via turbulence high-level for trarily large fields, using tip-tilt correction arbi- overachievable~0.”25 is of quality image median the that ensure will This error.anisokinetic negligible givinglevel a field, at deflection atmospheric entire the map to i-bands and r at stars guide enough are there that means Kea. This advantage20-fold enjoysa over, e.g. patch,isokinetic per C stars Dome guide suitable of terms that, in mean lectively col- sites existing over time coherence seeing,in gains and The angle isokinetic fections inthetelescope itself. imper diffraction, rather, by and/or than the median free (tip-tilt-corrected) seeing by limited be should conditions normal in of 0.4µm, imaging longwards wide-fields, the over that and conditions; best the in 1µm at images taking diffraction-limited of capable be should telescope the that are specifications imaging The we donotyet have (seeChapter3). layer, which boundary the of behaviour the of understanding full a on depends tiveconsider,to options efficacybuttheir attrac- both make parameterFried the of values largelayer the and boundary face sur fectiveness.the of height narrow The be undertaken during Phase B on their ef- layer at Dome C, and a full study needs to surface the of effect the mitigate to used be may systems tip-tilt and GLAO Both the free seeing. a level much smaller than that caused by tip-tilt,to and/or GLAO either rected,via bulenceabove cor be can telescope the tur layer surface any that so chosen be to needs height towerstudies. The such layerdary height, are needed as input for boun- the of layer,variability the on and varia- boundary temperaturethe of within tion of rate the both on data Further studies.B Phase through determined be tower,the of height however,The should A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) High sensitivityHigh near-infraredthe in - (ari and the visible in imaging Wide-field a such for specifications Performance Table 8.It would out- , Mauna - - - - e, l o tee r qie edl over design,mechanical proper readily as with come quite are these of all ver, Howe operation.- temperature room for and the operation of electronics designed changes;dimensional induced thermally to due change mayclearancesthat nical lubricants;mecha- of performance nued conti- the by dominated are cold treme ex- the by caused challenges design The is envisaged forgeneration. electricity installation power wind and PV 100kW A accumulation.frost and temperatureslow darkness,extremely wintertime continual chains,logistics extended with deal must operations lifetime and Commissioning access anddata transfer. and must overcome both limited physical communications, satellite via observing remote with run be to planned be must telescope daylight.The and darkness of cycle observing periods affordedlong by unusual the and environment polar the remoteness,its from arise observatory tic an Antarcof - operationalaspects Unique Roadmap andfunding • • • • • • • transmission). emission thermal and the high atmospheric from a combination of the low atmospheric (arising mid-infrared the and emission) spectrometer. field integral or FTS an as trometer, such layer tip-tiltcorrection. capabilities. These mightinclude: spectroscopic the enhance to seeing,or optical free-air superb the instance, for exploit,to instruments,designed 2 Phase Further instruments might then be built as commissioning camera. in the visible, which would also serve as a overrelativelyimaging mited fields small andlongwavelengthshort ranges. spectrometer, and two separate with arms aGRISM or Fabry-Perot filter tuneable a ments designedtotake advantage ofthem: in turn leads to an initial suite of three - instru gains performance these of Consideration cloud free fraction). high the and site C Dome the of latitude stable emission). atmospheric thermal scintillation) and the infrared (enabled by atmosphericthe low the by (enabled fraction limitatandlongwavelengths. short dif- the to matched scales pixel adjustable and correction GLAO / tip-tilt layer ground A wide-field,A spec- near-infrared imaging A wide-field, visible camera with ground li- diffraction for camera optical fast A A wide-field, mid-infrared instrument, with with camera, near-infrared wide-field, A high the to (due coverage Continuous High photometric precision in the optical -

into aninterferometric array. telescope the of integration possible the study,B Phase a in element tial well as as essen- and an is system GLAO a of performance operation the of Investigation lowerorderto reducedin be might costs. quality arelower.then image Similarly, on specifications view of fields the the as wavelengths, optical not and infrared at operation for only designed be to were telescope the if reduced be could costs instance,de-scoping.For any from result wouldthat trade-offs science and mance fully perfor options, to the the including all cost necessary are studies B Phase to costoforder 5M€ partner estimated the is instrument from Each countries. up made consortia builtindividualbyand funded are ments facility. Instru the share on time of observing of terms in return provide here Contributions agencies. polar national observatories, through support logistic and arethrough funded national support and management,development softwareject of the telescope structure and optics. Pro- M€ 20 of injection cash tial ini- an sees model funding possible One tional fluid dynamics (CFD)models. disruption – as demonstrated by computa- minimum suffers airflow external the and matchedclosely be can temperatures the is the delivery of excellent dome seeing, as scheme this of advantage point.further A saturation the below falling humidity its instrumentation,the heatfrom in resulting snow, and is heated using largely the waste the of surface the to closer from drawn is aperture.dome air the This at air external the to temperature sub-satu- in air, matched rated with flushed continuously be proposed. humidity-controlled is enclosure will enclosure This and temperature a humidity.turated problems,these To solve and level- supersa 30m),atthe even and ~0.15°C/m surface at temperature (~1°C/m gradient, vertical enormous the are C Dome at data astronomical of quisition ac- the to specific challenges major other the turbulence, layer surface from Apart will have adequate performance. thermal nal light weighted zerodur primary mirror indications are that a relatively conventio- (e.g. thermal mass low with substrates mirror nal unconventio- and considered, been has control thermal Active mirror. primary notably, the - requirements equilibrium with high mass thermal and tight thermal components for especiallyproblematic, more be can temperature of change of temperaturerequirements. rates high The the of account takes design the as long , silicon carbide), but current current but carbide), silicon , . . for the cost cost the for - - A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

The Milky Way, the Galactic centre and the Large Magellanic Cloud as seen from Concordia

Hubble ultra deep field black

41 42 Astrophysics at Dome C . • • • • • following oneyear itemsduring ofactivity. metre astronomy (WG2) has focused on the submilli- for 2 Group WorkingARENA The Working group activities • • sion,temperaturegra- and formation frost A knowledge of the atmospheric transmis- 2009. 2007, and the years 2008 in verified been have infrastructure telescope large deploymentfuture prerequisites a fora of necessary astronomy. The Antarctic for project new submillimetre very a project.is telescope It large the of status the of summary a provide to aims section This 4b astronomy A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) Roadmap andfunding. by industries. Preparation ofafeasibility study station upgrades. Study ofpossible Concordia Telescope selection. Selection ofsciencecases. modelling.Atmospheric Analysis ofsitetestingdata.

Submillimetre-wave also underdiscussion. are costs, running annual the of timates es- initial good as well as requirements, communication transportation,and ware hard- supply,nology,powerof the means estimate techof the cost - of the necessary being partners. industrial currently An the with discussed are requirements and specifications telescope study. The bility feasi- a starting before required are dient oefl o esr te luminosities, the measure to powerful particularly are observations continuum IR astronomy. FIR/submillimetre between radio and frontier the at astronomy of branch new relatively a is It galaxies. and planets, stars of evolution early and birth the unveil study and Universe’ to ‘cold the technique prime the astro- is nomy 1,000µm) to 100 - submillimetre FIR/ Far-infrared/submillimetre(hereinafter science andcontext Submillimetre astronomy:

interferometer on the Chajnantor plateau mm-wave (350µm-7mm) ground-based a observations.ALMA, science performing ched by Ariane 5 on May 14, 2009. It is cope now in Space has successfully been laun- tory,teles- (60-500µm) FIR/submillimetre a - astronomy?Observa Space Herschel The What is the context today of submillimetre metre astronomy. FIR/submilli- for drivers science potential polarisation of dust in the Universe are also evolvedin origin stars, and dust interstellar teroids,disks, debris formation, planet dust verse as well as that of galaxy evolution. As- Uni - early the to back history cosmic its of understanding an to and scales all at tion - forma star to of study lead the in primarily breakthroughs will telescope large with a wavelengths these at Observations abundances. critical and levels excitation their on depending illumination, UV and densities,temperatures different widely of regimes, chemical and sical These lines allow us to probe different phy- galaxies.of (ISM) medium interstellar the means to study the kinematical structure of only the are that lines molecular and mic atoseveral- in rich also is regime) (or THz spectrum the of range submillimetre/FIR 500µm.The and 60 between energy their of bulk the emit regions star-forming ded dust cold containing objects because dust of - enshrou- masses and temperatures ., regions regions i.e.,

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

COCHISE 2.5m dish in Antarctica might be able to operate in in set up phase all atmospheric windows between 200µm and 1mm, and very regularly at 350 and Table 9 Limiting sensitivity 450µm all year long. Performances for the observation of an astronomical point source located at 50° in Dome C potential elevation with the following assumptions: a and atmosphere transmission bolometer array camera installed on a 25m A major obstacle to carrying out sub- single-dish telescope with a total optical millimetre observations below 500 µm transmission of 50% (optics & filters), with from ground is the atmosphere as well as a bolometer absorption of 80%, with a noise the harsh environment of the potential equivalent power limited by the atmosphere under the 50% quartile of transmission. It ground-based sites (high altitude deserts; is believed that these hypotheses are repre- Antarctica). Preliminary meteorological sentative of realistic observations on Cerro studies and atmospheric transmission de Chajnantor in Chile (CCAT site) and at models tend to demonstrate that Dome C Dome C in Antarctica. could offer atmospheric conditions that open the 200µm windows. The SUMMIT08 Site 200 µm 350 µm submillimetre tipper (see Fig.2), a colla- Dome C 1000 mJy/s/ 60 mJy/s/ boration between CEA Saclay and UNSW/ beam beam Sydney, has started operation in early 2008 20 mJy in 1 h 1 mJy in 1 h to measure the sky opacity at 200µm. Using the MOLIERE model for atmospheric trans- Chajnantor 24000 mJy/s/ 200 mJy/s/ mission, it is possible to estimate the trans- 5600m beam beam mission at 350µm (see Fig.4). These results 3.3 mJy in 1 h confirm the transmission estimates using 1 mJy in 11 h radiosounding data by Valenziano et al. With these two sets of independent measu- Besides Herschel and ALMA, there is a rements, one can now state that Dome C is clear need for a large (>10m) single-dish currently the best accessible 3 site on Earth telescope operating at 30-450µm and in terms of transmission in the FIR/submilli- providing: metre. The 200µm window opens at a level • better angular resolution than Herschel of better than 20% transmission during 25% in the northern Atacama Desert, will soon • wider-field mapping capabilities than of the time (see Fig.3). About 40 nights of be available. Both facilities will have their ALMA, making large-scale mapping with observations at 200µm are expected with a specific niches. Herschel has the ability a relatively good angular resolution (~ 1”) sensitivity of 300mJy/s/beam for a 25m dish to carry out large-area imaging surveys of possible and well matched with the thermal telescope under the assumptions descri- both the distant Universe and the nearby infrared space telescope (e.g., Spitzer) and bed in the Table 9. Further analysis indica- interstellar medium in our own Galaxy. • bringing zero-spacing baseline data for in- tes that observations at 350 and 450µm are ALMA will make possible ultra-deep sear- terferometry and/or long baseline for VLBI. possible all year compared to only 30% of ches for primordial galaxies, as well as de- New sites are therefore intensively tested the time on ALMA site. A factor 11 in time is tailed kinematical investigations of indivi- because the 200-350-450µm windows at expected in favour of Dome C versus Cerro dual protostars. However, both Herschel Chajnantor open less than 30% of win- de Chajnantor when conducting observa- and ALMA will have their own limitations. tertime at an observable level, probably tions of a source at 50° elevation with a The Herschel telescope (3.5m) suffers less than 5% at 200µm. The stability of current state-of-the-art bolometer camera. from its only moderate angular resolu- the atmosphere is an equally important Comparisons with another site, Antarctic tion, implying a fairly high extragalactic parameter when comparing the sites, and Dome A, have been possible for a short confusion limit and preventing the study Dome C may stand out as being far more period of time based on a graph available of individual protostars in all but the nea- stable than Chilean sites. Equipped with rest star-forming clusters of our Galaxy. FIR/submillimetre imagers and spectro- 3 Accessible meaning that Dome C has a per- ALMA will suffer from a small field of meters, a European telescope at Dome C manent station with winter-over operation. view (10”) and limited observable conditions in the FIR/submillimetre, making extensive wide-field mapping impossible given the amount of time necessary to cover large star forming complexes and Fig. 2: fields of primordial galaxies. Precipitable water vapour Besides these two major facilities, there levels at Dome C are other submillimetre/FIR telescope from April projects in operation or under study, bal- to December 2008, converted loon-borne (e.g., BLAST, OLIMPO, PILOTE, from the transmission etc.), aboard an airplane (SOFIA), aboard measurements satellites (e.g., AKARI, SPICA) and on high- with SUMMIT08 altitude sites (e.g., APEX, CCAT). using MOLIERE Why consider potential science with a atmospheric FIR/submillimetre telescope at Dome C? modelling.

43 44 Astrophysics at Dome C . min arc- (FOV>>10 camera bolometer format large a including spectro-imagers with ped equivalent(or collective area)that equip - is diameter 25m of telescope a with reached be should objective this ranges, THz and starburst FIR the (NeII, OIV, detecting in lines OH…) spectral by and 450µm to 30 from luminosity bolometric galaxy the ring evolutiongalaxy overz=4. to z=1 measu- By in activity star-formation from holes black disentangle Universe,to the and in density rate formation star the of 50% than more of detection the is objective immediate The black holesandgalaxies The cosmichistoryofstarformation, Science case1: far-infrared astronomy DomeC at Science casesfor submillimetre/ the future (possibly in2011-2012). in telescope IRAIT the on array bolometer stability will be assessed with the CAMISTIC 450µm.and 350 transmission Atmospheric but no major gain is expected especially at 200µm,at better slightlywouldDome be A tellite dataset (see sa- NOAA MHS the with time of period le whopre-Heatthe - webpageforthe and on profiles, temperatures and masses, the core core masses, density the and 450µm,profiles, temperatures to 30 from luminosity tric bolome- core initial measuring function.By mass stellar observed and modelled the with it compare and function” mass “core a construct to Milky Wayorder the in ghout function down to sub-solar masses and throumass - core protostellar and prestellar the detection of the is objective immediate The The originsofstellarmasses Science case2: outthisproject. project issufficienttocarry 2-year time).A the of is 50% during that reached observation of hour one (in 1mJy around limit confusion the to down long year all 350µm atpossible are surveys large frared range. far-in- and mid- the Right: range. submillimetre ral PWV values using the MOLIERE code. Left: the seve- for C Dome at transmission Modelled Fig.4: or takenasabsolutecomparisons. reproduced be not should They indicative. mainly are Comparisons 2009. Frascati, Radford, Simon The CCAT site values are based on discussion with 5,600m. at site) (CCAT Chajnantor de Cerro for are boxes upper the 5,100m; at site ALMA the for yellow bars are divided in two: the lower parts are and Chajnantor (Chile). Note that the Chajnantor (Hawaii), Kea Mauna (Antarctica), Pole South the like sites other with compared are C Dome for 350µm at results extrapolated The PWV). vs. sion transmis- modelled using (extrapolated 350µm at and (measurement) 200µm at transmission tain Fig. 3: Percentage of time the atmosphere has a cer A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) 2 . k aes f fw deg few a of areas Sky ).

Fig.5). We conclude that 2 and hence hence and

- bolometer array (FOV>>10 arcmin format large a and beams) (min.ceiver14 re- heterodyne multi-beam with telescope equipped dish single 25m a with years 6 in achievable complete is LMC/SMC the of a mapping targets, these across limetre FIR/submil- the in mapping emission dust and regime THz the in surveys line lecular mo- galaxies. performing nearby By in and to prestellar cores, in the Magellanic Clouds the interstellar medium in our Galaxy down of properties chemical and physical the of knowledge the objectiveis immediate The The galacticenergeticengines Science case3: Chamaeleon) inoneyear ofoperation. (e.g. clouds molecular giant pletely com- cover to needed is submillimetre and far-infrared, mid-, the in spectrometer and (FOV>>10arrayarcmin2) bolometer format large- a with equipped thatresolutionis and area collecting equivalent (or dish 25m A nosity a on cores protostellar“lumi- the of position the as well as determined is function mass (FOV>>10 arcmin array bolometer format large a with ped improvementresolution,angular in equip - 12m dish or with a 25m dish to achieve an a with 2mm) to (700µm metre/millimetre submilli- the in group).Mapping working tion of state (synergy with the CMB ARENA rature evolution and the dark energy equa- Sunyaev-Zel’dovichof effects, tempe- CMB The immediate objective is the observation and darkenergy Galaxy clustersinthefarUniverse Science case4: vs. mass” evolutionary phase diagram.

2 ) isrecommended. 2 ). ,Carina,

Telescope requirements • • • • telescope configurations were studied: To fulfil the science case requirements, two Use of COCHISE as a first element of this this of element first a as COCHISE of Use selected. were interferometry bolometer if view of resolufield - the preserving tion, angular while better and area lecting col- same the offer would It dish. single large a to alternative an offer could and competitive be would (>>10) antennas many of array note,We however, an that observing best conditions inwintertime. the during manpower and maintenance of level high require FIRI: of would it pathfinder experiment a be achieved by ALMA. will 450µm and 350 at baseline.Science single a on hours of tens in 10mJy about delivering 200µm), at (~10µm atmospheric windows THz the of width spectral narrow the to due mainly is meter.This interfero- the of beam synthesized small allow detection of faint objects within the to sufficient be not will (10 200µm at hours) time of amount reasonable a after has beendismissedfor two reasons: meter configuration (three antennas only) interfero- selected.The was aperture,AST single dish telescope with a 25mdiameter finder for the FIRI space interferometer. path- a as The interferometer FIR/submillimetre diameter dishsuch asthe ALMA antenna. 12m a with obtained performance the with size, starting reasonable a to up limitation Extreme winter conditions for operating Poor200µm:sensitivityat sensitivity the a telescopes, small three of network A diameter no with telescope single-dish A A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

array should be studied as well as the Extension to mid-infrared installation of one (or more) medium- The large aperture of the telescope and size antenna(s) (6-12m), which might be high atmospheric transparency at Dome C adapted and built cost-effectively from offer unique scientific opportunities for already existing designs. Such antenna(s) high spatial resolution imaging in the MIR would constitute a necessary technolo- (<~ 40µm). The system wavefront error gical testbed and pathfinder for a larger budget of 12µm rms will not support dif- facility and would be able to achieve ex- fraction-limited imaging short of ~200µm tremely interesting science results of their with the full aperture of the telescope. own. The AST-25m telescope would pro- On the individual panel scale, however, vide a large collecting aperture with high Fig. 5: PWV contents at Dome C (white) and Dome the wavefront error is significantly dimi- A (red) extracted from the MHS NOAA satellite da- surface accuracy (<12µm) to operate at nished. Alternative options could be: (i) taset. The blue plot represents the SUMMIT08 data. wavelengths as low as 200µm, providing Red curve is generally below white curve. Note a Fizeau beam combination of many su- deep, high angular resolution (< 2 arcsec) however that MHS data give lower values of PWV bapertures (panels) spread over the disk images. The combination of the atmos- than SUMMIT08. would enable inteferometric image re- pheric transparency at Dome C and the construction with the full resolution of a large aperture would make this the most Optical design 25m telescope over a narrow field of view sensitive submillimetre telescope ever The optical design of the telescope is de- (as proposed for CCAT). (ii) Using the first planned. AST-25m would enable Europe termined by optical, mechanical and fo- (or first and second) ring(s) of panels of to be at the forefront of astronomical re- cal plane instruments constraints. It must the primary reflector would enable the search and would favour state-of-the-art enable efficient operations in the defined use of the telescope as a MIR single-dish instrumental development. AST could wavelength range and field of view (10-20 with the equivalent collecting aperture of also be used as a VLBI antenna between arcmin in diameter). As a baseline optical a 6.8m (10.8m) telescope. Either option ALMA and Antarctica, providing a base- design we have chosen, for now, the CCAT would require the panels (assumed here line of several thousands of kilometres. Ritchey-Chrétien optical system, with a to be 1.84m, square-like panels) to have Cassegrain focal ratio of f/8, a main reflector IR quality surface and an overall RMS of Note: telescope specifications and require- focal ratio of f/0.6 and a back focal dis- less than 5µm. Option (ii) would addi- ments are currently being discussed within tance of B = 11.0m. tionally require the first/second rings of the industrial partnership. An estimate of panels to be kept aligned to within MIR the cost of the necessary technology, the These parameters enable operations at specifications. power supply, means of hardware transpor- the Nasmyth focus of the telescope, and tation, and communication requirements allow a receiver cabin of the appropriate Roadmap and funding as well as initial estimates of the annual size and the construction of a rigid me- The necessary site conditions prerequi- running costs have been provided in May chanical structure (and elevation bea- sites for the future deployment of large 2009 at the 3rd ARENA Conference by the rings positioning) at an acceptable cost, telescope infrastructure have been tested EIE & Thales Alenia Space representatives. but then require quite a large subreflec- in the years 2007 to 2009, and are planned tor (~ 3m). This implies a possibly expen- to continue until 2012. A knowledge of the Top-level requirements sive secondary, and also a complex and atmopsheric transmission, frost formation This document presents only the top-le- expensive mechanism for nutating the and temperature gradient are fundamen- vel design or performance capabilities subreflector at frequencies of ~1 Hz. tal parameters needed before starting to needed to meet the science goals of this raise funds for a feasibility study. The teles- project. The science objectives require a Pointing and tracking cope specifications and requirements are 25m aperture to operate at submillimetre The diffraction-limited beam for observa- currently beeing discussed within the in- wavebands. Efficient operation at 200µm tions at 200µm is only ~2 arcsec, and poin- dustrial partnership. Joint efforts between implies the net effective surface error to ting and tracking a 25m telescope with Italian, French and Spanish teams within be less than 10-12µm so that telescopes 1/10th beam accuracy is a challenging the ARENA consortium, together with the would be able to find and track a source task. Achieving this goal will require ca- support of the IPEV and PNRA polar ins- with an accuracy of better than 0.’’2 arc- reful attention to all aspects of the mount titutes, led to the building and progressive sec. Therefore, there are four main critical and drive system. As with most radio teles- deployment of IRAIT, a 80cm infrared teles- areas that still need to be very carefully copes it is anticipated that a pointing mo- cope. One of the goals of IRAIT, as a newly- analyzed and discussed. del will be developed that allows blind installed IR telescope, operations will be as (i.e., absolute) pointing anywhere on the a path finding experiment for submillime- Active Surface sky to within one or two beam widths to tre astronomy in 2011-2012. It will perform Fabricating, setting and maintaining a allow for quick source acquisition and atmospheric and sky-noise measurements 10µm surface on a 25m diameter radio refinement of the pointing using bright with a bolometer array, prepare a catalogue telescope is probably the most difficult submillimetre sources. of source calibrators in the far southern sky, challenge for this project. It also implies and attempt several science observations that active surface control would be ne- The telescope must then be able to track of the Sun and of star-formation regions. cessary. Because the thermal distortions the target source to within about 1/10th of will be very critical at Dome C, it may be the beam for an hour or so before cor- In parallel, the COCHISE upgrade to ope- necessary to implement a dynamic closed recting the pointing on a nearby strong rate at submillimetre wavelengths should loop control system using sensors and feed- source. Because of the requirement to be studied, as well as the possibility of ins- back. This is commonly done at optical/ also observe during the day, it is desira- talling a medium size antenna paving the infrared wavelengths using edge sensors ble to achieve this pointing and tracking path to a future large telescope facility. Va- and optical instruments that measure the performance without a dedicated special rious complementary reports are available wavefront errors in real-time. offset (optical/IR) guiding system. at irfu.cea.fr/Sap/Antarctica. . 45 46 Astrophysics at Dome C . provided by IPEV. The group activity has has IPEV. activity by group providedThe was input which for constraints, rational ope- and logistical Concordia with tibility compa - the on put was emphasis ticular instrument.Parnulling combining beam the of studies for partly Space Alenia Thales at and ESA, for GENIE studied the instrument from derived Space Alenia Thales by concept a on out AMOS, based at carried was study engineering The from astronomers IAGL (Liège)andLESIA(Paris). by performed was analysis.spectroscopic study Thescientific nate sources suitable for future exo-Earth - discrimi to level) density dust times solar the (30 sensitivity required the with to exozodiacallight characterizationof the dedicated interferometer Antarctic an of study pre-feasibility a realize and define to was interferometry for (WG3) the ARENAof goal The Working3 Group Working group activities 4c interferometry A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020)

Optical andinfrared - be submittedtoFP7and/orESA. (1-2 study feasibility trial indus- full a for proposal a with forward couraging, so that we recommend moving en- ment. very are results preliminary The mechanism, top railway, and nulling - instru structure, with the snow,interface azimuth telescopes, the for proposals conceptual includes 2009.section JulyThis in report and tings deliveredAMOS pre-feasibilitya mee- different through coordinated been iesoig f uue x-at cha - exo-Earth future of dimensioning and feasibility the for dust exozodiacal by played role important the shown has exoplanets habitable of characterization infrared and discovery the study to dedicated ESA An objects. pho- those from of tons detection direct the and therefore analysis, spectroscopic a requires phere of potentially habitable exoplanets The detection of biomarkers in the atmos- Science andcontext M€ ) that could could that )

Unit Telescopes (UTs)isalso anissue. 8m the VLTon survey a such for required allocation time massive lity.the Securing integration into a less than optimized - faci Paranal, to due hurdles feasibility the and at seeing fast the to due performance in the validated science case but has has also shown the limits VLTI the at (GENIE) instrument an such implement to ESA by out carried mission.study space A future have the sensitivity needed to prepare the ferometer istherefore required which will inescapable. dedicatedA pathfinder inter is light exozodiacal is of issue defined, the mission characterizing exo-Earth an way coro- well. Hence, whichever as light nagraphs visible for significant is tion radia- dust exozodiacal to due noise This where exo-Earthscannotbedetected. sources on space time waste the not and on mission risk mitigate to order in thattargets, potential level,around sensitivity to down clouds dust exozodiacal 30 about than brighter clouds dust for detection jeopardize even may and exo-Earths, of survey the for source noise significant a tion, and its possible asymmetries, can be Earth.radia - Thisthe than brighter times zodiacal dust (1 by emitted flux infrared the of intensity example, the an as system solar the ring conside- Indeed, missions. racterization zodis. This calls for a survey of of survey a for zodis.calls This zodi by definition) is 300 - A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Artist view of ALADDIN and performance verification, the input catalogue of ALADDIN could be surveyed Dome C potential in two winter overs. After its primary mis- The Antarctic plateau may provide a better sion is complete, ALADDIN could either option. Extensive simulations have shown be dismantled or used for more general that at Dome C, an optimized interfero- science, if adequate support for exten- meter (such as the ALADDIN concept) ded operations can be found. Its obser- located above the turbulent layer would vational niche is the characterization of be more sensitive with a pair of 1m col- faint environments around central point lectors than GENIE with the ESO 8m UTs, sources, a common feature of many astro- and be compliant with the 30 zodis re- physical objects. It would be, for example, quirement. This is due to a combination an exceptional tool to characterize cir- of factors that make the Antarctic plateau cumstellar disks around Young Stellar particularly suitable for infrared nulling Objects, circumstellar matter ejected by interferometry. These are primarily: stars in the late stages of their evolution, • A large r0 above the turbulent layer (ena- dust tori around bright Active Galactic bling phased 1m apertures in L band wi- Nuclei, or even the K or L-band spectros- thout the need for adaptive optics). Based copy of a few close-in giant exoplanets on site testing data, the working group es- around very nearby stars. tablished that 18m is a reasonable height that enables the instrument to be above Instrumental requirements the ground layer about 40% of the time; When designing the facility, many chal- • Long coherence times which result in lenges have to be faced to deal with the much more efficient optical path length peculiar site conditions. control loops for ultra-low phase resi- duals between sub-apertures; • The first one concerns the interface • A consistently dry air which alleviates the between the facility and the ground. need for active phase dispersion control; Snow consists by essence of low-den- • A cold environment for reduced back- sity materials, and moreover that snow ground emission. moves due to the general motions of the Antarctic glacier. An Antarctic infrared nulling interfero- The Keck Interferometer Nuller has pa- meter would provide a performances ved the way towards such an instrument, competitive with that of a space interfero- by enabling the detection of 300-zodi meter concept such as PEGASE, while a disks in the thermal infrared (N band) at more compact space interferometer like Mauna Kea. FKSI would provide better sensitivity, at the 1-2 zodi level. However, the estimated The LBTI might improve these perfor- cost of a space mission is much higher Fig. 7: mances in the near- to mid-term future, (700 M$ vs 15-20 M€ for ALADDIN) and The track and although its final sensitivity to exozodiacal this added sensitivity might simply be an boggies prototype disks is currently unknown. However, as overkill with respect to the original ob- system at AMOS. for the GENIE project, these 10m-class jective. We see these facts as a formidable facilities at temperate sites will not be opportunity, both for the space programs The facility could be erected on three feet dedicated to an exozodiacal disk survey, (since risk can be retired on a major mis- similar to those supporting the Concordia so that the associated instruments will sion for a small fraction of its cost) and buildings (see Fig. 6). These feet have only partially fulfil the prerequisite for Antarctic astronomy in general, which already been built and people have ex- future Earth-like planet characterization would benefit from the momentum crea- perience with their installation on site. missions. It must also be noted that ted by such a project. Initial mission sce- As far as one knows, their behaviour is these instruments will only cover the narios considered by the WG indicate that, acceptable. The area on the snow surface Northern hemisphere. after an initial summer for commissioning is adapted to the maximum load allowed by the snow which is about 0.2 bars and to the weight of the structure which will be about 120 tons. Therefore, the three feet could support an annular track allowing for the azimuth motion (see Fig. 7). The diameter of the track has to be about 8m with flatness of about 1mm/m. The track is about 4m Fig.6: above the snow level and lies on a cylin- The six feet drical annulus designed to allow wind to supporting pass through the structure and avoid the the Concordia building. accumulation of snow. Three similar feet • The second challenge consists in kee- will support the ping the azimuth axis of the device in a interferometer. vertical or, as a minimum, stable position.

47 48 Astrophysics at Dome C . simplifications with respect to GENIE are: main The design. system optimised the ding atmospheric stability at Dome the outstan- by provided simplifications numerous account into taking trument ins- nulling VLTI/GENIE the of definition preliminary the from derived is 10, Fig. in shown design, instrument ALADDIN’s ber between thetwo telescopes. cryostatvacuumsmall situatedchama in - compressedaboutto the to diameter 2cm beams optical parallel deliver telescopes They have to be protected by domes. Both fications, telescopes. 1.4m nevertheless for speci- technical of kind same the having and AMOS by developed Interferometer design of the Magdalena Ridge Observatory Those telescopes can be adapted from the interferometer (illustrated inFig.9). se constitute the collecting devices of the the snow surface, two 1m telescopes. The- circulate,whichrailway on above18m at in (illustrated structure beam track.large supports,a latter through The design,this In rotatethe boggiesthree on performance tests in the AMOS workshop. in shown is project.ELTIt prototype for the azimuth axis of the ESO- been built under an ESO-EC contract as a track.the of plane has zontal system This - hori the of errors or slope the time real compensate thatin inclinometersbycan driven wheels active by obtained is This • • • A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) eoa o te iprin closed-loop dispersion the of removal removal corrector; ofthedispersion removal ofthelong-stroke delay line; during during 7 Fig. a a , 8) Fig. C and the telescopes of thesystem Top railway allowing to move. Fig.8:

control actuators); sensor, fringe (H-band control dispersion • • • the operational life, thanks to the exten - the during to life,thanks operational the on-site intervention human no with instrument autonomous and trolled remote-con- fully a for calls arrangement tic environment from each other. Such an Antarc- and instrument the protects also but cooling optics through optimisation performance provide only not does ber Design Study is started. The vacuum Preliminary cham- dedicated a as soon as rated - incorpo analysedand be should and ged envisa- are improvements tual:significant of design the that Note loop repetition frequency). closed- reduced (in significantly particular, loop control tracking fringe the on removal of the intensity closed-loop control; tog eaain f h requirements the of relaxation strong removal of the VLTI and interfaces constraints; is concep- is 10 Fig. • existing nulling breadboards: from heritage substantial enjoys trument the industrial phase is concerned, the ins- in development as far matters.As those in industry space the of experience sive • etc. A preliminary comparison with Cerro which will be soon selected for E-ELT,TMT, sites astronomical temperate best the at of performance atALADDIN and C Dome betweenmade be will rison expectedthe fore transfer to Dome C. A careful compa ment (and system) in a temperate site, be- - instru the of verification complete allow Later on, the autonomous design will also control ofanuller similar to very ALADDIN. perturbations to dedicated Observatory, is Alenia Spacelabs; chromatic non polarised nulling in Thales MAI² has demonstrated stabledemonstrated10 has MAI² NSld ESE i itgain t Paris at integration in PERSEE, CNES-led Fig. 9:Generalview of ALADDIN. -5 poly- -

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Paranal has already suggested that temperate sites cannot compete with Dome C for this type of instrument.

Although a precise cost estimate of the project cannot be provided based on this preliminary study, previous experience and comparison with similar projects suggests a total cost of 15-20 M€ for the project, including installation, commissioning and operation during two winters. The main foreseen impacts (or lack thereof) on the Concordia stations are listed here below: • transportation fully compatible with current Fig. 10: The ALADDIN nulling instrument design is greatly simplified wrt GENIE and can be accommodated into a cooled vehicles - total of ~110 tons to be transported; vacuum chamber of less than 1m³/1ton. • assembly of the structure during summer on a compressed snow area, carried zodiacal cloud density level around stel- represents the consensus of the interfero- out by five people, and fully compatible lar targets potentially harbouring exo- metric community in the post-ELT era. Other with current Concordia facilities (e.g., weight Earths, appears to be feasible (no show possible precursors (ICE, Mykerinos) have and height of the telescopes compatible stoppers identified at this stage of the been proposed but await both a definition with the Concordia crane); industrial study) on the Antarctic plateau. and a pre-feasibility study before further • one operating room at Concordia, with This appears to be the optimal location consideration. We therefore highly recom- an on-site supervising astronomer or tech- for such a facility. A typical height of 18m mend carrying out simultaneously: nician during winter-over (only part-time); above the ice is both sufficient, and prac- • average power consumption during win- tical, to operate free from the ground- • either a full size Phase A industrial study ter of 2kW per day, with a peak consump- layer turbulence. Key design challenges of ALADDIN as an example of a mid-term tion of 15kW, not taking into account pos- for the structure and instrument have Antarctic interferometry project or a joint sible frost removal device; already been addressed in the framework FP7 industrial study of common key ele- • high-bandwidth connection between of other projects. ments to ALADDIN and other projects pro- ALADDIN and Concordia, low bandwidth posed by the different working groups; connection with the outside world. The science objective is compelling for a • an observational confirmation of the medium-size Antarctic project. Such a fa- expected exceptional properties of the Conclusion and roadmap cility would also be a precursor to a high atmospheric parameters particularly rele- A nulling interferometer designed to de- sensitivity, imaging kilometric array alike vant to the performance of high angular tect and characterize exozodiacal disks, KEOPS (with full-sky coverage made pos- resolution systems (coherence time, iso- typically brighter than 30 times the solar sible by the large isoplanetic angle) that planetic angle). .

An example of the success of near-infrared interferometry: measurement of the orbital revolution of the companion of theta Orionis made with the instrument AMBER at the VLTI. (Kraus et al., 2009, A&A 497, 195).

49 50 Astrophysics at Dome C . the three main ARENA conferences. at organised were discussions further and was held in Catania,Italy, C” Dome in fromSeptember 2008 observations “Time-series vations at Dome C. A dedicated workshop obser such perform to projects of series a reviewed and observations series time ted the potential of Dome C for astronomical The ARENA Working Group 4 (WG4) evalua - Working group activities pnd w frhr ra o research of using time-series: areas studies of stellar activity further two opened detectors,have electronic with available became that precisions higher much the by driven mostly developments, recent med to investigate variable stars, but more cally, such observations- Histori have investigation. been perfor under objects the of behaviour temporal the about mation infor in resulting taking data of process continuous the as time-series define We Science andcontext 4d photometric observations A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020)

Long time-series - - - that is obtained; or for the detection of of detection the for or obtained; precision is that and coverage frequency the to restrictions serious pose interruptions daily space, where frequency into series reliableobtain to transformationstime- of of thefollowing requirements: several or one include typically projects time-series state-of-the-art done, be not could previously that things do to able the scientific advance coming from being of part planets.extrasolarlarge of a With characterization and detection the and consideredpreviously stars ‘quiescent’in • • • eurd n ay contexts; many in required are observations continuous Long sites. limiting one for observations from normal The requirementfirst is certainly the most have beenlittle explored todate. often incombination withhighdutycycles bevtos n pcrl ags that ranges spectral in Observations Very good seeing and/or low scintillation Long observing coverage in stable conditions,

e.g. i order in ,

observations. time-series on dependent are that cases science many of requirements the meet emerges therefore as C an alternative that may better Dome maintenance. of lity impossibi- the and cycles,development cost,high long very disadvantagesof the MOST,CoRoT, Kepler, etc., SOHO with but as such projects space-based from came limits these circumvent to step globe. further A the around sites good of bution - distri uneven an and issues calibration disadvantages:ral coordination,complex HATnet). Networks present however seve - PLANET, GONG, (e.g., sites temperate at networks from observations by satisfied been has cycles obser duty high long with vations for need this In cases, probabilities.some interruptions detection their any lower where events, rare observations have to be performed within not.The or obtained be can interruptions daily brightness if week-long coverage without sky- maximumpermissible the on pends de- mid-winter. So, it at even present is cle C.Dome at obtained However, a be may cycles duty high with runs ving obser winter, long Antarctic the During Observing coverageanddutycycle Potential of Dome C with significant twilight around noon around twilight significant with eurs ht all that requires cycle seasonal daily cy- daily - -

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

ASTEP set up (2009)

photometric precision over longer observing spans. Variations in sky-transparency, such as faint dark cirrus at high altitudes, would also affect precision photometry. Their effective influence is however unknown at present. Confirmation of the quality of sky transparency should be The small an urgent action and a principal topic IRAIT telescope of the currently employed photometric instrumentation. Detection and characterization of extrasolar planets Spectral range The detection of extrasolar planets via tran- Dome C may also allow ground-based time- sits in front of their central star allows the series observing in spectral ranges that are determination of the planetary radius and barely exploitable in temperate ground - if combined with radial velocity measu- sites. One refers here especially to observa- rements - their mass and mean density. tions in the near-to-mid IR and in the sub- Thanks to the possibility of long time-series millimetre wavelength range. Observations observations with high photometric preci- of the sky brightness at 11µm made during sion from Dome C, the detection of smaller the summer at Dome C showed that the planets than achievable with comparable sky stability is exceptionally good. In the instrumentation at normal sites should IR range from 1.5 to 14µm the background be possible. Furthermore, the low IR sky- brightness at the South Pole is up to an brightness at Dome C may give a unique order of magnitude lower than at Mauna opportunity to search for transiting planets Kea, one of the best temperate sites. Such around small late-type dwarf stars (types low background emission clearly favours M and K) in the NIR, where these stars are time-series observations in bands like K, much brighter than in the visible.

L, M, N and Q, with the Kdark band around 2.4µm showing an especially good combi- Photometric planet detections are also nation of low sky emission and good trans- possible from surveys of stellar microlen- about 7 months per year. The combina- parency. At Dome C, the corresponding sing or from the detection of variations tion of observations from Dome C with background brightness and its stability are in the timing of periodic photometric those from a network of telescopes at tem- however essentially unknown and should signals. From Dome C, the microlensing perate sites may, however, be considered be better characterized before serious method may detect planets down to the for projects that require year-round or per- investments are made. mass of Mars in orbits around either G to manent coverage. The weather conditions L-dwarf central stars or around giant pla- at Dome C favour also high duty cycles, nets in these systems. Detections from the with suitable observing conditions up to timing of photometric signals may be di- 87-98% of the time, values that have never sentangled in the highly periodic p- or g- been reached by temperate-site networks. mode pulsations of subdwarf B stars and white dwarfs, in the eclipses among binary Accuracy stars and in transits of known planet-star The major impact from the presence of the systems. Similar to transit searches, these Earth’s atmosphere comes from scintilla- methods will greatly benefit from long tion, which generates variations in the num- observing spans under good conditions. ber of photons from a stellar object that Using a combination of techniques, it is fall into an instrument’s aperture. Dome C possible to measure the mass and orbital has the lowest known scintillation noise distance distribution of planets, and the from any site on the ground. Scintillation frequency of planetary systems; several of is mainly due to light paths being bent Artist view these methods (e.g., searches for transits by turbulences in the higher layers in the of ICE-T and microlenses) may be joined into sin- Earth’s atmosphere - hence photometric gle observing projects. experiments that require high precision Science cases may benefit from a location at Dome C The science cases that were considered, The characterization of known transiting even if mounted without a tower i.e. , at given in more detail below, may be put planets (e.g., detection of atmospheric ground level. Scintillation in infrared and into two groups: detection and characte- constituents, secondary transits, reflected other spectral bands still requires further rization of extrasolar planets, and stellar light) has delivered spectacular results in site testing. Seeing, which is mostly caused studies (asteroseismology, stellar activity). recent years from both ground and space- by ground-layer turbulences, is in general Additional science cases may include based observatories and the importance less important for time-series work, since e.g., Gamma Ray Bursts, Active Galactic of this subject may only be expected to it affects photometric precision only as a Nuclei and Quasars, up to moving objects increase. Characterizations may be done second-order effect. We note that the non- like Near Earth Objects and Trans Neptu- with high-precision photometry, optional- negligible diurnal cycle also has to be nians. We note that solar studies are treated ly in multiple colours, but the highest po- taken into account for any estimations of in Section 4f. tential is in spectroscopic observations.

51 52 Astrophysics at Dome C . pointed out: therefore are cases science keyfollowing The constituents. atmospheric planetary of detection transits,the for secondary or detecting by planet the of light direct the conditions, stable uniquely under performed be also NIR-MIR,the in may observations rization larger. or characte- spectroscopic and Photometric 2m of telescopes using other sites) at cycle diurnal are the (which by degraded hours 5 about durations than longer transit with planets periodic long- of planet-characterization for nities - opportu unique expect C,we Dome For stable atmospheric conditions is essential. very of presence the precision,and high day,a about few very to require up but hours a between duration, shorter of are observations characterization general, In *3. Aperture (Telescope aperture) (Telescope aperture) *3. Aperture Notes: Table 10Science casesandrelated projects A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) Stellar activity(characterization) Stellar activity(detection) Long-period pulsationvariables Asteroseismology Microlensing (tracking) Microlensing (detection) Exoplanet timing(detection) Exoplanet characterization Exoplanet transitsearch(detection) *1. Method for the measurement of of measurement the for e.g.,

Phot: photometry;Spec:spectroscopy.

Small: 0.5m;Mid:0.5-1.5m;Large:>1.5m. CCD phot CCD phot CCD phot CCD phot HiRes spec CCD phot CCD phot CCD phot CCD phot IR Phot CCD phot, IRPhot Method* HiRes spec HiRes spec transits. planetary site toobserve is anideal Concordia *2. FOV(FieldofView) 1 • • • • and characterization Key science for extrasolar planet detection eald netgto o te hsc go- physics the of investigation detailed the allow will measurements, trometric to spec- high-resolution and interferometric addition in targets, bright nearby of observations Doppler precise space, to structure. interior stellar the of Compared determination high-precision a thus and inversion, structure mode precise more telescope.small a with a even yield They than photometry, have a much noise better activitySNR, stellar the by affected less data,observations.Doppler resulting The spectrometric through done be will stars Kepler, solar-like and of observations CoRoT ground-based by conducted as observations, photometric space-borne to Contrary stars. solar-like for ways ted limi- but,far, very diagram so in sell only - Hertzsprung-Rus the of the strip in instability stars bright for ground the reached from been has goal This precision. coverage,time continuous ultra-high and are extreme, requiring high cadence, long However,requirements observational the unravelto techniqueinteriors. tant stellar impor most the undisputably is mology Asteroseis here.- considered are activity stellar of studies and Asteroseismology Stellar studies

of theplanethoststars. characterization ofthestellaractivity extrasolar systems characterization oflong-period and/orspectroscopicphotometric around Mstars small(faint) detection ofextrasolar planettransits extrasolar planets and/orsmall detection oflong-period Wide Wide Wide Wide Small Ultra Wide Wide Small Wide-Ultra Wide Small FOV* Small Small 2

*4. Time duration

Ultrawide: >>1deg;Wide:Small:arcmin. Aperture* Mid Small All All Mid Mid Mid Mid-Large All All Large All

Typical lengthofcontinuoustime-seriesforagiventimeresolution. 3 Resolution Time 10min 10min 10min 10sec 10min hour 30sec 1min 10min 1min 20min 10min

- Duration* Time Months Days-Months Months- Years Months Days Months Months Hours Months- Years Months Months Months curves curves in at least two bands are light needed to precise very Hence,temperatures. but cannot determine true spot areas and size, in variations their follow and tudes longi- spot determine only can data light white- stellar modulated rotationally of Consequently, anymore. inversions rable and shape of the light curve are not sepa- amplitude observed the and termingled photometry,effectsarethereforethese in- the “blue”white-light of part.case Forthe to than moreplages and bandpass the of the to contribute will spots and “red” part time,Sun,same our the does at plagesas chromospheric warm and starspots ric photosphe- cool has star solar-type pical light.However,ty- white are a in out carried transit-searches photometric most availablephotons,all of use make to der lar-like and likely spotted host stars. In or so- around detections exoplanet precise more and more of light the in important particularly is This topology. magnetic key expectedingredientsforthe internal stellar rotation rates which are among the of measurement precise the enable also activity. stellarStarspots of tracers table detec- easily most the are sunspots, as magneticfields.stellar starspots, Cool just strong of signature the is rotation stellar to due modulation its and activity Stellar red by CoRoTandKepler. these targets will only marginally be cove- here, as proposed also is pulsators dwarf series of photometry subdwarf B and white Earth.the aroundTime- all sites 8 least at proposedas projectbySONG requirethe such instruments ground-based rate-site In order to compete with Dome C, tempe- verning the stellar structure and evolution.

4 Possible project SIAMOIS ICE-T,IRAIT ASTEP400, ICE-T ASTEP400, ICE-T ICE-T PLT ICE-T ICE-T, ASTEP400 IRAIT,PLT ASTEP400, ICE-T, PILOT PLT,SIAMOIS SIAMOIS -

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

separate spot and plage effects as well as compositions to magnetic activity Summer use to perform solar full-disk to constrain the spot-temperatures and the • Monitor quantitatively the activity imaging is also being contemplated, with stellar limb darkening. Dome C represents of planet-host stars the ASPIRE instrument. German funds here a unique opportunity for photometry • The impact of stellar activity on to construct this instrument have been that is directly astrophysically interpretable. the evolution of planetary systems obtained and commencement of observations at Dome C is aimed for by 2013. Key science for stellar studies Instrumental projects However, its relocation to Concordia and Asteroseismic observations for time-series observations the funding of its operation is at present • Doppler observations of solar-like still in need of being secured. oscillations in cool bright stars and in giants Instruments in the development/ • Doppler observations of pulsations construction phase • SIAMOIS is a ground-based asteroseis- in d Scuti, g Dor, PMS stars • ASTEP400 is a 40cm telescope dedica- mology project to pursue Doppler velo- • Interior structure of nearby stars: ted to exoplanet transit detections. Its field city measurements from Dome C that will primary parameters, age determination, of view is 1ºx1º and it is specified to reach achieve a scientific programme comple- composition a photometric noise of 3mmag per acquis- mentary to CoRoT and Kepler. The core • Convection; diagnostic of convective tion, reaching 1mmag during one hour for of the instrument, providing the neces- cores; depth of convection and at least 1,000 stars. For at least the first years, sary sensitivity and stability, is a Fourier of second helium ionization zone; ASTEP400 will require human intervention tachometer similar to the helioseismic damping, excitation mechanism for winter operation. The delivery of the network GONG, fully automated and wi- • Non-linear physics, saturation effects, mode whole instrument to Dome C is scheduled thout moving parts. SIAMOIS may first ob- coupling; stochastically excited modes in 2009. It is currently being set up. serve with one dedicated collector, then • Comparative study: photometry/ with two collectors feeding the Fourier Doppler techniques • ICE-T is a 0.6m double optical/near-IR Transform interferometer. To enlarge its • Time-series photometry of subdwarf wide-field robotic photometric telescope. potential, one of these collectors should B and white dwarf pulsators Its core scientific objective is the detec- be a 2m-class telescope like PLT. The high tion and investigation of the combined duty cycle accessible for the spectrome- Stellar activity observations effects of extrasolar planets, stellar ma- tric observation of bright targets, a crucial • Map the short-term evolution gnetic activity and non-radial pulsations point for asteroseismology, is comparable of starspots and plages on the structure and evolution of stars. It to the best space-borne observations; the • Determine spot coverage as a function is designed to perform time-series pho- photon-noise limited performance, about of stellar rotation and age tometry of approximately 300,000 stars 1 to 10cm/s, is comparable to 0.1 to 1ppm • Observe and quantify starspot decay in a single circumpolar field of size of in photometry. Funding for phase B needs • Relate photospheric chemical 8ºx8º during several Antarctic winters. the roadmap for Dome C to be fixed.

The IRAIT telescope at Concordia

53 54 Astrophysics at Dome C . tralia andEurope. betweenAus venture- joint international an as (PLT)PILOT of version a propose to progress in are agencies.Discussions funding Australianthe by supported not in successfully 2008 but the following phase B study finished was was PILOT of capabilities of the site. The phase A study intended to exploit almost all the unique instrument multi-purpose a com- is been It pleted. has C Dome at tower 30m lescopes that are open to the community. Dome C requires also the provision of te- of potential the of development full The ter time-series, toweeks. lastingfrom hours shor with performed be can trument,but the need ins- 2m-class“large” a of aperture cases science key some since instrument PLT a for support is there projects, these observations. time-series troscopic Beyond spec- and photometric long-term for basis instruments dedicated providethen the will SIAMOIS) and (ICE-T Future and (ASTEP400 IRAIT). C Dome for phase tion - construc their in instruments ad- by dressed be already can cases science Some proposed.one oftheinstruments by forwardserved put be dateses can to ca- science main all that note may One inthefollowingdescribed paragraphs. are phase planning the in or construction 2009. Theprojects that are currently the in mid of as status C,their Dome lists at observations and time-series involving jects pro- the of overview an gives 11 Table Roadmap andfunding • Early-phase projectstudies (1deg wide-field 2.5m a in resulting study sign de- A telescope. optical large national inter an for pathfinder a Australia,by is PILOT,earlier the proposed from project Notes: Table 11 dependent onresolvingissuesofsite-accessandinternationalcollaboration. A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) PLT sIRAIT SIAMOIS ICE-T ASTEP400 IRAIT ASTEP South PAIX Project The Polar Large Telescope (PLT) derived

(or similar2mtelescope) *1. CDR 2 O) pia/R eecp o a on telescope optical/IR FOV) Status of the projects Statusconsidered of this roadmap in

Conceptual DesignReview. P P P P … … … … CDR* * 4 1 *2. PDR P PDR* 2012 2009 P … … … … - - 2 Preliminary Design(PhaseA)Review. P 2014 2010 2009 … … … … FDR* 3 Secured Financial status In preparation In preparation funded Construction Funded Funded Funded Funded 2009-2010 2009-2010 lead tothefollowing roadmap: C time-variableDome fromon phenomena science top-level for projects major The • • • Stars) is graded dedicatedthe top priority of Interior the in Oscillations Measure to solutions.Deployment shouldbearound 2013-2014. need issues operational site-access and but funded, is Its construction studies. activity stellar for reference a become to expected is and C Dome at rity instrument for time-series photometry Telescope) has been granted the top - prio 2013-2014 larger scale projects. towards steps fundamental form they as priority with treated now be must ments com- will mence observations and in 2010. These - instru 2009 in delivered been has ASTEP400 2009. in implementation delivered to Dome C and waits for on-site been “accomplished”has projects.IRAIT and IRAIT SIAMOIS (Seismic Interferometer Aiming Explorer Concordia (International ICE-T r considered are ASTEP400 *3. FDR Installed Logistics status Under design Under design On hold Preparation Operable Installed Removed

Final Design(PhaseB)Review. * 5 2010 (2yrs) 2018 (6yrs) duration operation of First science year and anticipated 2013 (4yrs) 2013 (4yrs) 2010 (4yrs) 2008 (2yrs) 2008 (?yrs) 2007 (2yrs)

enclosed in an insulated vacuum vessel (in purple). requiredsurethe performance, inteferometerthe in- is to order In instrument. SIAMOIS the of Design • Beyond 2014 ged toinclude specificdimtargets. telescope, 2m-class enlar be will return scientific its a with SIAMOIS feeding phase, 2014, with two small collectors. In a second studies. Its Doppler deployment is foreseen for 2013- stellar in reference to the expected become is and C Dome at troscopy spec- time-series advanced for instrument long-term perspective.long-term the in observations time-series to dicated precursor for a telescope of similar size de- sources.fainter PLT on may alsobea valuable or precisions, higher with time-scales shorter on observations time-series form per to community scientific the to access give open should It instrument. gramme multi-pro- future a as cornerstone a red PLTLarge(Polar conside - Telescope) is *4. P

Passed. *5. . funding forPhaseB planetary systemGliese 581

Artist’s impression of the newlydiscovered - -

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

55 56 Astrophysics at Dome C . However, ter, unexplained dark by verse, cision based all (CMB) verse luable are surveys, answer thesefundamental questions. ge-scale mology: At Precision CosmologywiththeCMB the uniquepotential DomeC of Precision CMBmeasurements: Cosmic have 4e A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) dark matter, consistent well-constrained the expected matter

through entered filled on information beginning Cosmic

observations

and Microwave CMB experiments

sensitive structures even an with and of with adiabatic to SN-Ia in the dark energy. if the radiations, Microwave provide this dark standard of a measurements era expansion standard on parameters, cosmological through Background, the model can energy of these inflationary 21 enough Precision produce

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A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Fig 11: The “Bullet Cluster” (1ES0657-556). X-ray plasma emission is in red, while the blue blobs indicates the position of dark matter (identified by means of the gravitational lensing).

The windows at 95, 150, 250GHz are evident. Atmospheric emission in this frequency range features brightness temperatures of a few K in the best windows. This means that advanced offset removal techniques have to be used for anisotropy measurements, starting with beam switching at Fig. 14: Optical depth of the atmosphere at 350 constant elevation. In this respect, the real microns, measured during the same winter period killers for these measurements are atmos- in Dome C (grey) and SP (black). pheric gradients and instabilities, related to turbulence, wind and so on. The linear very low turbulence. Radiosounding and polarization of atmospheric emission at extensive testing at 350µm have shown these wavelengths is quite weak, and is an average optical depth lower at Dome C generated by the Zeeman effect of Oxy- (respect to SP) and, moreover, the average gen lines in the Earth magnetic field. This wind is a factor 2 lower (see Fig. 14). also produces a much stronger circular polarization. Here the killer is low-level At these frequencies, diamond dust and conversion of intensity and circular pola- seeing produced in the lowest 30m of rization into linear polarization inside a the atmosphere are not as relevant as in real polarimeter. This disturbance, however, the optical range. At the South Pole, scans

is proportional to the stability of the O2 of the sky at constant elevation are also atmospheric emission. constant declination scans. It is thus impossible to perform cross-linked scans, as would be required for an efficient map- making procedure. Constant elevation scans carried out from Dome C, instead, change their tilt angle in the sky by +14° The 10m South Pole Telescope, already in 24 hours, allowing an efficient drift funded by NSF (tens of millions USD), removal technique. For polarization ex- and the BICEP polarization experiment periments, this is a very important bonus, testify the importance of CMB observa- allowing measurement of the same pola- tions and the recognized necessity to rization direction in the sky with different use the best environmental conditions to inclinations of the principal axis of the fully exploit their potential (see Fig. 12). polarimeter with respect to the ground. In fact, the signals to be measured by pre- Fig.13: Atmospheric emission (top) In this way an important test for polari- cision CMB experiments have an antenna and CMB anisotropy (bottom) spectra. zed ground spillover can be carried out, temperature of the order of 1K or less, with which cannot be done at the South Pole. a spectral brightness peaking at 220GHz. The advantages of Dome C In the same frequency range atmospheric The Dome C site (3,202m asl) is higher Both Antarctic sites share the advantage, emission is due to rotational transitions of than the South Pole (2,900m asl), and is with respect to low latitude sites like Cha- water vapour, oxygen and ozone. A sample on top of a wide dome, while South Pole jnantor, that it is possible to follow the model emission spectrum is compared to is on a slight slope. This results in a more same sky patch for the full day, thus al- CMB fluctuations in Fig. 13. stable atmosphere, with weaker winds and lowing extremely long integrations with almost 100% efficiency. Due to the day- night and fast elevation change of sources, in low latitude sites the efficiency is lower by a factor 2-3.

This feature is extremely appealing if one wants to focus on the very best sky patch in terms of galactic foregrounds. The so- called BOOMERanG region, observed by the BOOMERanG experiment in 1998 and 2003, features extremely low H and dust columns, and is very conveniently located for observations from Dome C. This region can be observed continuously for Fig. 12: SPT (right) and BICEP (left), two CMB experiments at the Amundsen-Scott South Pole station the whole winter, and for most of the sum- (from www.usap.gov). mer without interference from the Sun.

57 58 Astrophysics at Dome C . A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) ordinates). (same unitin polarization (B)] tion (E),B-mode E-mode polariza- [temperature (T), of observables correlations represented the bottom are From topto and polarization. CMB anisotropy power spectraof rements ofthe Current measu- Fig.15: bolometric features: ments to QUBIC configuration, more B03 bolometers pected very treme Pole, ted or posed a to polarization include The the measuring current consistent gns that B-mode A bolometricinterferometeronDomeC Proposed projects • • • • grail” A diate been ment. few in three areas: Therefore, inpolarimeters emission(multi-band andtracers) andintegration limiteddetectors time lating at mental systematics indirect imaging different already is will reason, tant cal modeled a “ground ted clean diation, large much rious Reduction ofsystematic effects Knowledge ofpolarizedforeground Sensitivity: Angular detector reliable. the different Dome all number coherent properties advanced signal are at feed-horns,

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A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

A large dish for millimetre/sub-millimetre astronomy and cosmology High-resolution observations of secondary anisotropies in the CMB and of early galaxies and dust-obscured AGNs in the millimetre range are of considerable interest. The South Pole Telescope (SPT) is fully devoted to the observation of CMB photons scattered by rich clusters of galaxies. These observations can be used to study Fig. 16a: The BRAIN-MBI 144 detector module concept. the physics of clusters of galaxies and to The horn array is visible at the top-right. After modu- use distant clusters as probes to measure Front page lation by the phase shifters, the beams are combined the cosmological parameters, via the Hub- of Nature with an off-axis telescope. The bolometer array is coo- (April 27, 2000) 4 3 ble diagram for clusters, cluster counts led down to 300mK with a He/ He refrigerator. advertising and the measurement of TCMB(z). the success of the BOOMERanG SPT will carry out outstanding measure- Telescope in ments.The main concern in this kind of Antarctica measurements is that the internal structure of the hot gas in many distant clusters sources of electrons: baryons, dark matter, of galaxies will not be resolved by SPT. relativistic plasmas. Many galaxy clusters In fact distant clusters of galaxies have contain, in addition to the thermal IC gas, a typical angular diameter of ~1 arcmin, a population of relativistic electrons that roughly independent of redshift. Only produce a diffuse radio emission via syn- the closest clusters, at a redshift less than chrotron radiation in a magnetized ICM. about 0.05, have larger angular sizes. SPT The electrons responsible for the radio Fig.16b: Signal to noise ratio for the baseline configuration of the bolometric interferometer. is using an optical aperture of 7.5m in dia- halo emission have energies of a few meter, which is large enough just to match GeV to radiate at frequencies higher than the size of the clusters of galaxies: the no- 30MHz in a magnetic field of a few µG. for radio (5-20GHz) near the cosmologi- minal resolution is Dq 1.’’5 at n=95GHz, Dq The origin of such relativistic electrons is cal CMB window and in the millimeter 0.’’9 at n=150GHz, Dq 0.’’6 at n=225GHz, not certain: they can be produced throu- wavelengths (above the cosmic CMB but the reconstructed beam size is a bit gh a re-acceleration process by IC turbu- window). There are a plethora of experi- larger (~1.’’2 at n=150GHz). lence, or can be created by the annihila- ments coming up, and it is quite clear that tion of dark matter WIMP. The presence of one expects, for example, proper disco- In order to resolve the intra-cluster (IC) extreme UV / soft X-ray excesses in a few very and mapping of spinning dust emis- structures, a larger dish is required. The nearby clusters indicates the presence of sion around 10-20GHz. Although it is not case for a 30m millimetre/submillimetre an additional population of secondary a primary scientific goal, as the B-mode dish in Antarctica has been discussed for relativistic electrons or a combination of and SZ effect are, it is also important for a long time ago. A telescope of this class, warm and quasi-thermal populations of Dome C to have secondary science pro- complemented by a large focal plane distinct origin. Further evidence suggests grammes operating and complementing array, can provide the necessary informa- the presence of additional electronic these observations already scheduled. tion from spatially resolved clusters. As a components with peculiar spectral and It will be a perfect location to produce matter of fact we know that the electron spatial characteristics. small absolutely calibrated experiments, distribution of the “atmosphere” of the ga- producing small samples of sky that laxy clusters is various and complex. Among them there are: non-thermal hea- may work as calibrators for foreground ting in the cluster cores, AGN and radio- maps. The community needs much of It is a combination of several populations galaxy feedback, intra-cluster cavities and these to control polarized foregrounds. of thermal and non-thermal distributed radio bubbles filled with relativistic non As an example of the importance of this electrons with different energy spectra thermal electrons, multiscale magnetic fields. issue, in 2008 the INSCAF (International and spatial distributions. Each one of the Examples are given in Fig. 11 and Fig. 17. Network for Scientific Cosmological Ana- electron populations produces a distinct Finally physical arguments suggest that lysis of Foregrounds) has been created, SZE with peculiar spectral and spatial annihilation of Dark Matter candidates involving several projects in the radio features. There are three matter compo- can produce secondary electrons with a and millimetre foreground surveys. nents in clusters that provide different spatial distribution, which in massive clusters is strictly related to that of the original Fig. 17: Cluster DM, giving information on the DM mass MS0735.6+7421 as and physical composition. seen by Chandra (left) and the There are currently only upper limits to same cluster with the non-thermal SZE in the literature de- indication of the rived from observations of galaxy clus- central back hole and the two cavi- ters which contain powerful radio halo ties, where there sources or radio galaxies. The problem is a population of detecting the non-thermal SZE in ra- of hot gas coming dio-halo clusters is severe because of the through jets. associated synchrotron radio emission, 59 60 Astrophysics at Dome C . electronrious populations. higher The res one frequency experiment. on rized asfollows: the cross-over, weeks, thermal led at DomeCin2006(see support realistic the measurements tely tallation, refill thepulsetubewhen required. are BRAIN rator In port the been more • • • • This A bolometricinterferometeratDomeC Feasibility which instrument installedatDomeCin2006. Fig. 18a: The BRAIN laboratory and the pathfinder The phases, of minate ring At experiment. sional mechanical also theoccasionalhelpofbase staff. A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) Site. Consumables. People. Power. this higher the site and Concordia elevated logistic atmospheric produced. combination the both is snow experiments completed chances The

operated

access

laboratory demonstrating laboratory a is at plus spectrum, the angular laboratory cycle 15 to summer

SZE. A growing

medium-size a band frequencies,

to low in instrument recognize kW team cylinder berm negative

requirements

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to base continuous frequencies and The can to 4-5 successfully resolution For the by of installation windows

detect to no technique of a of there 15m has at years. be 4 the is a 30 only the pulse-tube of part electrical, high this dangerous intra-cluster the 350GHz to the 3

already should that already He in easily experiment gaseous kW above in Antarctic the installation 6

are is A of the size. effect fluid running can the refrigerator frequency

researchers full for the

for above Fig. 18a). first required, the signal could would and done positive in (see has

the 250-300GHz be at able the the In be been

time logistics wood part necessary cryogene- helium spectrum. of materials principle 0.3K practice, plateau). upgrade modera- summa- Fig. 13). the first plateau full - structu already of the also to of with conta- on instal- of allow occa-

non- with sup- part and and SZE size has ins- the du- the the va- for of to in a

being readied for launch (2003) BOOMERanG Telescope The

logistic storage This for at is and can the used tes/day, munication experiment isrequired for command. • • being and been should ces ture ofabout 16°C. temperature of Table 12 GHz. ItisidealforfutureCMBandmm-waveexperimentsfromDomeC. to a large number of pixels while being readout by two coaxial lines for a carrier frequency around a few able to break Cooper pairs and modify the resonance frequency of the resonator. The system can be scaled are photons 140GHz where resonators, superconducting close-packed are sensors The Italy. in boration colla- RIC-INFN the by produced pixels) (81 array (KID) Detectors Inductance Kinetic of Array 18b: Fig. Angular resolution RAIT Frequency Cost and timescale. Communications. estimated the Dome real data raw does is be wireless successfully used perfect one BRAIN

from support to time be connected unit needs data not C. be “control”

installed very A for

monitoring; channel stored should include located at for observatory. second to communications all a our successfully be at rate

the A The safely

through the container transmitted Dome be in purposes. total to from at hardware “control” of this kept instrument

station, increase a the one on cost

low-speed The cost C). Europe optical site. at main around or

at northeuse

A is At a

laboratory power Dq (arcsec) n (GHz) container to

and A two subset tempera- Dome installed (already the the second Europe station produ- to fibers labor. com-

GBy- 3 time and size the M€ of C

interest of costs This astronomy andcosmology(AST) A largedishformillimetre/submillimetre topublication)start isplanned: cies. group group analysis plementing veral of development A These meter) for Sunyaev-Zel’dovitch science. 90, format resolutions the Table 12. 90 23 30m-class

the this 150,

is A laboratories must arrays refers station a

class 150 eto 4b) Section (see full 220, arrays 4 of very of be cycle the

to 340, the telescope such at to are large evaluated time and 220 be (1,000 9.4 . Dome the CMB

feasibility 450GHz under of in achieved a personnel size (10 submillimetre Europe the telescope community 270 7.6 detectors C, permits years). development project by

experiment but and the of (see Fig. 18b). for as 340 6.1 confirms

travels. or The Station 5years. a the reported with a with per a telescope detailed working working in spectro- angular

450 a 4.6 These (from band, agen- in com- large long the

se- in

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

strip of the sky mapped by Planck Planck by mapped sky the of strip A map of the sky with the superimposed superimposed the with sky the of map A during the First Light Survey (13/08/09-27/08/09).

61 62 Astrophysics at Dome C . that relatively solar ven The conditions. capable cently programmes, ted explore Mid was seeing mer, WG6, andoganizationactivities Working group goals, potential Following dy ofallother blessing rife (September 4f A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) (March

Term the task formed the and remarkable,

observations together formed

conditions Solar astrophysics short potential the of of to was of less Review preliminary

the define 2007) exploiting 2007), in Dome implications

the particularly time ARENA working groups. detail ARENA with December EC.

main unusually of and of

a the The had allotted, of C WG5, first the the than presented Potsdam subjects 10-member Dome work working those main

been project, Dome mid-size

challenging is of 2007, for

and the on good, the task favourable C studied night-time of

meetings C

the after group: with most in at the suspec- the site facility was

group Tene- solar solar sum- fact stu- the the for

re- gi-

to in it

CNRS electronically. cility anditsinfrastructure (tower). the provided Petersburg large meetings meetings Discussions issues, at for infrastructure, gineers Meudon members tings, were The filing anddesign. well conducted Capodimonte coronal design as discussions

polar normally often management andreporting, and on outside for in support, (at Observatoire facility (e.g. and in science meetings, involving were discussions Catania instrumentation,

July ARENA at ,

held breadboarding Observatory the

at on the

also and allowing 2008), and the and each

formal by like University held scientists infrastructure conferences de instrumentation, sub-group

Observatory on Frascati, and, SCAR specific Paris-Meudon during in

list science, towers for

of particular of at and of of science

course, and the . etc.) larger Saint- issue mee- WG6 Nice pro- and and

en- - fa as of at

Technology resolution An vations low is (<500-600hours/year); provide ted been The nuous observations. Current and ground context Solar astrophysics the space in spatial the system New on will vations in duty-cycle small GOR Upcoming limitedspectral diagnostics.with very observations. or cally “poor”). the the off-axis time resolution example duty next-generation however working telescope Solar designed values is resolution IR, other are are solar since more generally cycle

and Coronagraphs (e.g. problem facilities either Telescope design) foreseen, Solar hand,

at it of and is facilities than Diffraction-limited have ,: (the to will

cannot at the NSST the the (like used provide very Telescope

reasonable Tenerife are Adaptive a limit not (with limited are of large

planned Fried few but

at THEMIS) “lock” limited less at usually and for AO provide of currently La the Big hours diffraction-limi- with than on-disk either facilities and the parameter, activation

sites Palma) Optics when (ATST) capabilities duty 1.5m Bear. in small, Advanced noise the a the and of coronal few spectral on-axis cannot in seeing cycles. obser

obser

conti- same -

They 1.6m GRE-

or have AO with typi- % that, and use,

of in at r o - - -

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

also in the IR or NIR, allowing observations at the opacity minimum (1.6μm), in lines formed at the temperature minimum (CO lines at 4.5μm) or sensitive to the Chromosphere-Transition Region magnetic field (lines at 12μm); in addition, the pro- minent coronal forbidden lines of Fe XIII, MgVIII and SiIX at 1,3 and 4µm could also be observed with high signal-to-noise (S/N) ratio, thus allowing direct magnetic field measurements and determination of electron densities from line ratios (e.g., the Fe XIII lines in NIR: 1074.7/1079.8nm and 3.388/1.0747μm). a Dome C unique assets for solar observations ARENA studies have shown that atmospheric optical parameters at Dome C during the austral summer are excellent and typically even better than in winter. Furthermore, the surface turbulent layer, or TGL (Turbulent Ground Layer), is exceptionally thin: it is of the order, on average, of 32m or less, and, in summer, has the interesting peculiarity of almost vanishing for a couple of hours during the afternoon, as shown in Fig. 21 (seeing data taken from the Concordiastro platform - about 8.5m above the ground - from November 2003 to December 2008). however, will only deliver high duty cycles Moreover, our work in the course of WG6 with a state-of-the-art AO system - a subsystem studies has shown that these positive of the facility that is yet to be confirmed. aspects are not offset by the relatively low solar elevation at polar latitudes (at It is clear, therefore, that, an Antarctic solar Dome C, the Sun is never higher than facility providing high angular resolution, about 40°). Adopting simple but realistic polarization and direct coronal magnetic b assumptions about the turbulence of the field measurements in the near IR, is a de- atmosphere above Dome C, we estimated Fig.19: that for observations of the Sun above finite complement to current, upcoming, - a: Fine-scale structure pervades the Sun’s chro- and planned solar facilities. mosphere. Here, flare loop / small prominences 15°, the seeing should be degraded by seen in the CaII H line, extend from the chromos- no more than a factor two with respect When considering space instruments, an phere up into the lower corona. The rich struc- to observations at the zenith. Antarctic facility also finds its place be- ture and waves results from the hot, ionized gas cause it could achieve very high angular (jets, spicules) interacting with the Sun’s magne- The right-hand panel of Fig. 21 shows the resolution observations of the chromos- tic field, noticeably through motions, «wiggles», seeing from the Concordiastro platform de- phere (following HiNODE, and much initiated by turbulence at or near Sun’s surface. rived from such a model. It is evident, thanks before larger missions in 10 or 15 years to the periodic disappearance of the TGL - b: This image shows the corona structure up to like SOLAR-C, Japan, or HiRISE, Europe - in the afternoon, that it is possible to reach six solar radii. It is impossible to obtain an image exceptional seeing values towards the sun proposed for ESA Cosmic Vision and of such quality from either ground based eclipse intended for the second phase of the observations or with SOHO LASCO C2 coronagra- (~0.’’6) for a couple of hours every day, from programme), and complementary to the ph. Ground based observations are influenced by just a few meters above the ground. only coronagraphic mission to fly in the the Earth’s atmosphere and the contrast of coro- coming years (expected for 2013-2014): nal structures at a distance of six solar radii is so The same condition of free-atmosphere the ASPIICS ESA PROBA-3 mission. The low that it cannot be significantly improved even seeing is attained during the entire day by latter, however, is limited to the visible by sophisticated mathematical methods. On the observing above the TGL at elevations of at range. Moreover, space missions are prefe- other hand the SOHO coronagraph, and Lyot co- least 15°. In this case, it would be possible rably targeting the UV or far IR range. And, ronagraphs in general, has its «blind area» near to reach at Dome C the exceptional value the Sun up to 1.5 radii since affected by diffrac- of course, space instruments are nearly of a Fried parameter r >12 cm (corres- tion of the internal occulter («artificial Moon»), o ponding to seeing < 0.’’84 at 500nm), and impossible to maintain and improve. and poor resolution. The excellent seeing and e sky brightness of Dome C and the large telescope this almost permanently during the 2,000 An Antarctic facility, therefore, would be design of the AFSIIC coronagraph gives a unique hours of Sun visibility above 15° (see Fig. highly complementary, by providing quasi- opportunity to obtain high quality images of the 20). This is almost a factor 3 more than the permanent high resolution in the visible but inner and middle corona. best mid-latitudes sites!

63 64 Astrophysics at Dome C . high-resolution scale, order order (flux res chromosphere-corona But, ofcoronal heating.derstanding thus and complicated energy more, dominates rent to gas red tive photosphere, minating have by that a atmosphere the energy between The tarctic at facility DomeC. exploiting face: studies physics The vided Taking Solar science cases and assets science and 15degrees,respectively 10, 5, 0, of red, elevation minimum to the refer lines elevation; black and solar magenta, orange, of function a as hours, in cycle, Duty 20: Fig. A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) region a two

the pressure losses solar to first dynamics waves

ground the understanding have situation at

to solar in which tubes of of in into of sustain may of can very study cases orders needed two pass set Concordia where 20km energy the the the kG) corona: the account the in great modes (b of also classes chromosphere effectively programmes, high with dynamic (the

- over intermediate magnetic can <<1 the through interactions where of chromosphere-corona outside science unique of where the on or of the imagers, to be significance magnetic input the chromosphere be

in angular the so. magnitude convection and magnetic current it their corona. as (see plasma heat reflected. the

addressed, b suffices solar Hence the outlined magnetic the

engine the sunspots potential cases much be is to field

Table 13), corona).

interface

intrinsic the spectro-imagers the and and physics resolution magnetic chromosphere, balance chromosphere between carried

region, flux goes Moreover, concerns the (b is of

field corona The of to ratio future that for in the zone)

broadly >>1 the pressure) - of elements the the need Table 14. from mention

exceeds is Further

our heating

unique we out spatial of several an of of waves of in requi- requi- radia- space outer diffe- inter such field

and link will An- the the the the the do- the un- the get for by di- - -

lar is innermost troscopy mosphere concerns energy rona The mosphere-corona interface. forward 12μm NIR long high with vide. of instrumentation or all and sing over Modelling dissipation.lead toenergy life low of cence the mutual Table DomeCfor 13Principalassetsof solarobservations for extendedperiods oftime Medium-High Angular Resolution High AngularResolution Infrared @highS/Nratio Asset different magnetic observational future those there emergence, cycles second

diagnostics “paradigms” their angular the at magnetographs, In temporal its region, and that larger interactions that in excellent last of space-borne is approaches evolution the is 0.5 subduction from and the has a the set heats flux dominated respect,

resolution, promises years growing heliocentric solar exploration

investigation coverage, of dynamics, inner restructuring

significantly up that elements, can constraints, for key the potential and to

and radii and this an

in only corona: are that and science corona the evidence to below

the delivered 2003 toDecember2008.(Left)Correctedzenith;(Right)towardstheSun. November from data with created Histogram ground). above 8.5m platform, ber through March), as function of the time of the day (from the Fig. 21: ConcordiastroTwo-dimensional histogram of the seeing at Dome C in summer (Octo- by high Antarctic

possible dissipation. scrutinize be easy of

badly twist, in little distances. ground-based

a via partially can extended

a the of that in physics order duty

the progressed that major in and objectives access

2D the explored shearing, terms monitor solar in that - particu surface current coales- facility, promi- cycles, could to acce- spec- chro- need their

step pro- that The But the folco- at- to of

M-HAR HAR IR(2) IR(1) Label at should lerates ning on Once and atmospheric conditions). cal tospheric Ejections key in to quires with (R<2.5R derstanding for corona Understanding dium toblack holeaccretion disks. systems inner coronal kinetic, to wind rameters understood. knowledge the ticular Dome the plasma the establishing ground questions processes latter, the present more, acceleration, corona corona, Sun,

SOHO, the the and the sun is ranging origins magnetic C

and ) ≈ ≈ 12μm 1-5μm Main parameters convective (CMEs) physics important

would direct an solar 1800 hours/year @<1” 700 hours/year @ <0.’’6 preliminary other

magnetic in (strongly about full of Space low

Antarctic remain and have magnetic that space, its physical of this a from characterization wind corona stars, be baseline measurements that space dynamics, convert

coronal originates field transport and greatly missions, complex a

not unanswered. motions. energy and affected the

and major is coronagraph and indications CMEs, processes weather, directly remains field. instrumentation only interstellar it even advanced of Coronal heating, astrophysical

into

step are plasma and this

in knowledge

system The for Regarding by but more

not subpho- thermal, relevant but forward,

elusive energy explai- of in of An seeing of in

physi- based many Mass solar fully also par me- our the the the un- the pa- re- so -

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Table 14 Key science cases, methods, means and Dome C relevant advantage Science Methods Primary Science Cases Major Dome C Assets Instruments IR(1) IR(2) HAR M-HAR Magneto-Hydrodynamics of Sunspots & Magneto-seismology x x •ASPIRE (2010–...) High Angular Dynamics of Fine Structures in Chromosphere/Corona Interface x x x x AFSIIC (2015–...) Resolution • A-FOURMI (2020–...) Local Helioseismology x • Coronal Magnetic Field x x •Single Ø50-70 cm 2D Coronal Coronal Dynamics of Fine Structures x x off-axis AFSIIC telescope Spectroscopy for coronagraphy (2012-...) Coronal Seismology x x •AFSIIC (2015-...) excellent quality of the sky for coronal 30m, i.e. ,on a tower. In order to be able to lengths, multi-heights) between imaging- observations be confirmed. Such an asset bring to the community a versatile facility, spectrometer and high resolution spec- will be enhanced by the excellent seeing capable of both very high resolution and trographs. We require PERMANENT dif- to provide high S/N observations that will coronagraphy, we facilitated access to the fraction limited performance at Dome C, allow access to the inner corona, very primary focal plane by having off-axis with seeing as “bad” (!) as 0.’’8 at 0.5µm near the limb. In particular, direct magne- telescopes. This makes the design more (8.5m above ground: probably 0.’’5-0.’’6 at tic field measurements, for instance via full complex but, once more, coronagraphy 30m). This means a maximum ro of 12.5cm Stokes polarimetry of the Fe XIII 1,074.7 & in the IR is a major asset of Concordia. and an 8x8 elements deformable mirror 1,078.9nm lines, will benefit from the qua- for a more than perfect correction of the lity of the site at Dome C. Instrumentation for high 500mm primary pupil (could work also angular resolution with a 700mm pupil). Proposed facilities and infrastructure Solar interferometry, studied in R&D pro- One key advantage of the Dome C site grams with ESA and CNES (3-telescope When phased by adaptive optics, individual is the thinness of the turbulent ground imaging breadboard with fine pointing, telescopes can then be cophased 3 by 3 to layer (about 30m). By observing above phase control and image reconstruction 0.’’08 for a triplet (AFSIIC) and 0.’’025 with the that layer, it is possible to access directly on the Sun and Planets), has the advan- full 3x3, 4.3m A-FOURMI interferometer. One the free-atmosphere seeing - and with an tages of compactness (size), cost and of the 3 telescopes - at minimum - is equip- “open tower” to avoid “tower seeing”, alike mass, while delivering on operational ped (rotator on optical train) for coronal ob- the Dutch Open Telescope at La Palma. control and image quality. In the case servations and could be installed first on the of a compact interferometer like the platform as soon as 2012 (ASPIICS support). Since a further interesting parameter in- one proposed for AFSIIC, the image re- fluencing the design is the wind profile construction is straightforward since it Solar magnetometry and wind speed, particularly favourable at consists of a simple division by the opti- Another very important aspect concer- Dome C (always lower than 14m/s), we de- cal transfer function. The interferometer ning instrumentation at Dome C is the cided to use an open telescope approach. has been extensively studied (structure direct measurement of the magnetic field and recombination) for use in Antarc- from the photosphere to the corona. Two We therefore choose an open frame tower tica at Concordia (proposed for the Eu- techniques allow for detection of both of 30-32m with appropriate damping and ropean FP7 programmes, infrastructures strong and weak coronal fields, and are control to stay above the TGL; an open and space, in 2008). The compact de- therefore appropriate for observations at telescope(s) structure to limit telescope sign benefits from the thermal venting a site like Dome C: and mirror seeing; an Adaptive Optics sys- by slow “laminar” wind through open • Zeeman effect and scattering signatures tem to phase the elementary telescope tubes (carbon-epoxy). Off-axis mirrors of magnetic fields in forbidden (magnetic pupils when very high resolution is loo- allow NIR coronal access. Plus: there is dipole) coronal emission lines; ked for (<<0.’’1); and a cophasing system no dust at Concordia, only ice crystals • Hanle depolarization of permitted to phase a triplet of telescopes. Open that will not deposit on the “hot” SiC mir- transitions in coronal atomic ions and in tower, open frame, open telescope. rors (anti-frosting issue). Heating and strong lines in prominence plasma. cooling are of concern at Dome C as in Debate on using a tower or GLAO (Ground space (deep space radiators at -80°C). The Hanle effect is mostly interesting in Layer Adaptive Optics) results from the SiC, highly conductive, also allows gra- prominences, in strong lines (Ha, HeI supposed difficulty of raising a 20-30 dient control and focusing. 1,083nm), and allows the vector magne- tons 2-2.5m telescope to the top of a 30m tic field to be determined. tower. Instead, while GLAO systems have An interferometer is compact and uses, not been tested yet and are offering only simply, three telescopes of smaller diame- The NIR Fe XIII line at 1,074.7nm presents a partial correction, approaches do exist ter (easier to manufacture and control) a factor of 5 advantage over the Fe XIV for designing reliable towers appropriate to achieve, with phase monitoring and a at line 530.3nm, and there is a definite for the Dome C needs, as we have shown. delay line to adjust optical path, the same interest to extend the wavelength range to In the solar case, and since coronagraphy performance as that of a “large” telesco- 4µm to include the Mg VIII and Si IX lines. and magnetometry are foreseen, we also pe. We propose an innovation in terms of Ideally, and even though Fabry-Perot ex- need to avoid the adaptive optics train the operational modes by having the possi- periments are already difficult, it is worth to minimize reflections when observing bility, like with HiRISE (ESA Cosmic Vision), adding the extra complexity of the NIR at the corona: this is possible directly for of using the Ø500mm telescopes directly 1µm and of the IR extension up to 12µm a significant fraction of the time only at (and simultaneously, therefore: multi-wave- (since compatible with optical coatings).

65 66 Astrophysics at Dome C . a dedicated These tion (SodiumandPotassium cells). re and developed will science throughput ofthefacility. trumental the magneto-optical or tial, imaging, ASPIICS. in Three Instrument package anticipated instrument: the relay perature be (and placed chromator with (visible be nagraphic solution triangles withtelescopesatthecrossingpoints. of(cophasedtriplets, madedown)byA-FOURMI - telescopes 9 the or up) - (AFSIIC telescopes 3 the of bon-Epoxy structure) and stiff telescopeCar and mirrors support(SiC design triplet On-axis 22: plateFig. A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) double and the a used

combined atmosphere beams high magnetoseismology allow combination balancing either mirrors major focal three chromosphere

simultaneously directly Second, and coverage spectral 2D mode or box to mode magnetic from

(SDM) at triple as plane a a major spectrograph, a instruments IR), in (shown together telescope like Capodimonte subtractive versatile to them).

to filter, the the a

and behind FP), where (SDM using infer or, high-resolution of or for any instruments three

entrance

alternatively,

field AFSIIC. alike will using temporal a ASPIICS

in They the in to of as triple in 2D use in a pink be

are the maximise telescopes a double the the the measurements providing the wave the Fabry-Perot, two can spectroscopy

very used. First, to Observatory, on considered photosphe- of Fabry-Perot telescopes instrument AFSIIC and prefilter individual resolution heights are, therefore optimise propaga-

, Fig. 22) the through

high spectro-

Third, a mono-

Super each, coro-

tem- box, spa- can ins-

re- of in

is a -

At perature mosphere inversion fits 30m presents only 40m can for three graphy power complementing cost, posed (seeFig.23). solar 30m red, and The the 4mInterferometer(A-FOURMI) The ultimatefacility: servations (ICE-T/ASPIREinstrument). next adding ATST face. resolution Various to thefreeatmosphereseeing A 30mtowerforaccess small-telescope approach. AFSIIC Operations Solar the Concordiaon station Logistic footprint summertime, the ~200 mostly rotating polarization). study 300 In ternoon, optics Besides magnetic fieldmeasurement. <<0.’’1, directly of at high principles plets, sea waves, is feet to terms 4m telescopes this ±

from level. and high hours

bypass

coronagraphy be Antarctica with tower.

although A-FOURMI resolution 2 above step off-axis facility combined

in observations watts

of using this mirrors spacing, requirement hours. combines from coronagraphy, and devoted time, the

designs behind in of high device the the

gradient resolution The the in six

the after time seeing for Operation particular manpower, are the coronagraphic

at natural the rest the magnetoseismology active solar

recombined presented

seeing Ideal petals By resolution chromospere-corona tower, so raising at the we train,

fine retained: Dome at we to 4m AFSIIC. the is the of to afternoon (fixed of the ground. going Dome that high and very 2 panels directly simply ultimate momentarily provide the ones, ofsolarpanels. towers systems the for are pointing

gain high of telescopes, temperature Interferometer

naturally still with same

alike reaches synoptic but

time of

stay we 8kW chromosphere power resolution, high coronagraphy time

to C/Concordia. relay: done

C, has

From the are having resolution, capacities flux (much) instruments Other its

nine which estimate telescopes go have because the comparable mode way. of when direct below in fine or resolution, Facility (16-20 an also and high-stiffness

the only to no available the and full may addition so, one Concordia telescopes

The estimated been without sufficient initiatives, structure vanishes. three generate

adaptive in gradient conside-

the tower, variable lower what coronal corona- with Sun 0.’’5-0.’’6 free during hours) spatial

to the triplet waves of come is bene- while same inter

tem- on 260- pro- and that The

the are ob- the i.e., - tri re-

at- af- its to to in at at a a -

cility magnetic tion-photosphere-chromosphere-corona projects mate quality, with are concerns: pm.fr/ARENA. are ment qualification More coverage, chromosphere magnetic process ofthemid-sized rimetry, conditions, with providing It axis telescopes. Coronagraphy) Imaging and Interferometric Solar for cility mables, measurements This and corona, & support): on ve at and assembled telescopes one For brightness, and more recommends capabilities, and tion Concordia an built astorage/maintenance hangar. recognising patible The Conclusions station, red scaffolding tower is coronal high the 8 the

for highly available definitively one maintenance th of ARENA duty for first spectroscopy continued could container 2D information, one to high concept, turbulent

the summer

with sky is resolution, chromosphere-corona and magnetoseismology the for that

Dome

medium-size

it cycle built etc., link”. spectro-imaging,

A-FOURMI. will very access, encouraged tubes, field

site: in and low to electronic,

will resolution is brightness, andwaves. be 1.4 telescopes the the the WG6 could of online:

their mount a AFSIIC

necessary probably four

and

directly excellent possible upgraded is and high instruments water C surface of As activity provide to high

solar 12m in the unique junctions measurements

required

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A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Fig. 23: 30m tower designs square tower, hexagonal with feet and an optimised compromise between the Amans’ tool tower and the hexagonal one, with a double structure for stability (hexagonal heart), ease of assembly with reduced scaffolding and large accommodation for the telescope platform (8m in diameter with 1 m height free). Tubes’ section can be adjusted to the maximum anticipated load but a nominal 40 tons tower (not including the feet) with 10 and 20 tons loads was considered for modelling. Note that the plateau can move up and down thanks to the three winch engines, allowing maintenance of the Solar Facility but, also, to change facility between summer, AFSIIC or A-FOURMI, and winter, e.g., with a 2.5m, 20 tons, PLT telescope.

Sunspot observed with the Swedish Solar Telescope (SST). This image in G-band (430nm) shows the transition from the dark umbra of a sunspot toward the solar granulation. The penumbra in-between shows filaments with central dark lanes.

67 Logistics and polar constraints Logistics

68 The Dome A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020). of ASTEP delivered at Concordia

5 Logistics and polar constraints 5a Astronomy at Dome C and logistics

The future possible he objectives of the ARENA programme, with respect to the logistics establishment of an of construction and operation of an Tastronomical infrastructure at Dome C, astronomical observatory are to identify the specificity of the logis- in Antarctica is fully tics for transporting, building on site and operating the proposed instruments. The dependent on the subjects addressed by the NA4 action can be summarised in six areas: transporta- capability of the logistics. tion of equipment, construction of the ins- The French and Italian trument on site, logistics of consumables, environmental considerations, medical polar institutes have aspects, and telecommunication needs. IRAIT demonstrated their The analysis of the instruments proposed (IEE) should be conducted for any new capacity to build, maintain by the 6 working groups, performed by the infrastructure at Concordia. Such an IEE French and Italian polar agencies, IPEV should provide information on the pos- and operate together and PNRA, has led to the dismissal of sible impact of the activity on the envi- the Concordia station concerns with respect to environmental ronment. If the conclusion of the IEE and medical aspects; no major environ- demonstrates that the impact would be all year round. ARENA had mental threat has been identified in the more than minor or transitory, a Compre- proposed experiments, and no additional hensive Environmental Evaluation (CEE) an activity (NA4) aimed at medical problem beyond the usual at- should be initiated and evaluated, at the evaluating the feasibility tention for the welfare of a limited crew international level, by the Committee for is involved, in the present formulation of Environmental Protection (CEP) of the of implementing the proposals. However, according to the Antarctic Treaty. Such a CEE was neces- the astronomical projects Annex I of the Madrid Protocol, it is noted sary, for example, for the ICE-CUBE pro- that an Initial Environmental Evaluation ject at South Pole. This report will mainly proposed by the working consider the areas in which the present resources for Dome C operation are be- groups. NA4 presents the lieved to be challenged by the proposed results of their evaluation, experiments and are therefore limited to the more technical areas of: made through close • transportation of equipment during instrument installation and transportation of cooperation between Installation of the Concor- consumables, essentially fuel, during rou- scientists and polar diastro tower tine operation of the instrument, (2003-2004 • on site construction of the experiment, and operators. Summer • telecommunication with respect to data Campaign) transfer in the operational phase. 69 .A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020)

An analysis of the instruments proposed, which offer an optimal blend among site characteristics and advanced scien- 5b Plan tific objectives, leads to a preliminary grouping of experiments in three categories, with respect to demand on logistics: small, intermediate and large. These for the installation three categories refer in the following analysis only to the expected impact of the instrument demand on the available of a large instrument capabilities; small instruments request the use of capabilities as available presently; intermediate instruments require limited upgrading of present capabilities; large instruments need major upgrading. he sequence of operations for the ins- ship cannot approach the Dumont d’Ur- tallation of large, heavy equipment at ville base early enough in the season, Dome C consists of several phases: when the ice is still extended. T• transportation from the country of ori- The equipment that is traversed to Dome C gin, to Hobart, Australia, where the French with the first traverse must be stored in The Twin Otter ship Astrolabe is loaded for its trips to Dumont d’Urville at the end of the pre- that services Dome C from Dumont d’Urville, the French winterover vious year and winter over there. It is to be Mario Zucchelli base on the coast of Antarctica. assumed that at least two Antarctic sum- station. • transportation from Hobart to Dumont mers will be needed to move the equip- d’Urville. The maximum dry load capabi- ment from Dumont d’Urville to Dome C. The same instrument proposed may fall lity of the Astrolabe is around 300 tons, but in different categories for different as- this is more a function of the volume and Construction at Dome C will imply pects of the logistical impact. One may the individual weight and volume of each devoting a certain number of techni- need limited support for one area of lo- parcels. The ship crane capacity is 32 tons cians for the whole summer season to gistics, and larger support in another. A at 8m and the maximum volume of each the construction of the experiment. A preliminary categorisation is given in the parcel is 4x4x10m. A typical 300 tons ins- number of five people is quoted as suf- following. The categorisation is based on trument will have to be split into two trips. ficient, and this is to be compared with the declared characteristics; these are so- • traverse from Dumont d’Urville to the amount of manpower necessary for metime insufficiently described because Dome C. The traverse load capability is the construction of the base itself. A large of the early stages of the projects; the fi- typically 170 tons, and it is to be assu- astronomical instrument is equivalent to nal category for each instrument may be med that only one half of a traverse can one of the two towers, and the estimate of modified after more careful design, and be devoted to a single experiment. It will five people can be checked against that concerted transport, construction plans therefore require four traverses to carry a to evaluate the amount of time required and operational routines are identified by 300 tons instrument to Dome C. to erect such large instrument; three sum- the proposing teams and the Italian and mers of construction are to be planned. French polar agencies, PNRA and IPEV. These will most likely be in series with the transportation, and only partial over- Obviously, the small instruments are lap of the two phases can be expected. easier to accommodate. ASTEP and IRAIT An expectation of three years from start fall naturally into this category. It is to be of transportation to Antarctica, four years noted that IRAIT, even being “small”, took from start of the transportation from Euro- several years to move to Dome C. It is pe to the beginning of the operation can now entering the operational phase. The be evaluated. It is also important to consi- main lesson learnt with the IRAIT project der the lifting equipment on site, which is that logistical and technical aspects is not convenient today for erection of must be carefully considered in advance high or heavy installation. Such equip- to avoid any delay in the phases of trans- ment must be integrated in the projects port and construction. The routes These phases are repeated three times and added to the total cargo to be sent to from Italy per season. The first traverse generally Concordia. It is not possible to determine We can categorise the proposals as follows. to Dome C. cannot transport equipment that arrives the class of such crane, given the insuffi- SIAMOIS and ICE-T are to be considered at the beginning of the season, since the cient information available at this early small, and present no major challenge stage of design. for installation and operation at Dome C, in any area of logistical support. The solar As regards consumables, the transpor- interferometer is to be categorised as an tation requirement during instrument intermediate instrument with respect to operation will be to move from Dumont logistical impact.The category of large d’Urville to Dome C the fuel that is nee- instruments, among those proposed by ded to power up the instrument during its the ARENA working groups, comprises The French operation. The requirements stated in the the PLT, the ALADDIN and the submilli- polar ship available documentation range from a few

Logistics and polar constraints Logistics metre large antenna. . Astrolabe. kW, to the maximum 90kW of ALADDIN. 70 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

We will assume 20kW as the average PLT, and not realistic for ALADDIN, with the bandwidth of 256kbps. A specific word of requirement, with the expectation that current capabilities. The requirements for caution is to be said with respect to ins- this may increase during final assess- the submillimetre telescope are not availa- trument positioning at Dome C. The large ment. In the case that this requirement ble. The current Concordia telecommuni- instruments are generally requested to be increases towards a maximum of 90kW, cation facility offers a data dial-up connec- in a place where no exhaust fumes disturb the implication may be that a new dedi- tion service capable of transferring up to the observations; the request of using the cated power plant should be necessary several megabytes every day at 10€/MByte. clean areas cannot be accepted. Two po- for the astronomical instrument. The fuel The system implemented at Concordia is sitions may be recommended: either on needed is to be evaluated as 0.23kg of based on the Inmarsat satellite fleet and the radius Concordia - the American tower, fuel per kW of consumption. The anti- does not support a permanent link chan- or on the opposite direction (Concordia cipated power consumption, typically nel unless MPDS or BGan Inmarsat devices – summer camp). It appears likely that 20kWh, assuming an operational duty are used. MPDS protocol devices demons- astronomical instruments will prefer to be cycle for the instrument of 50%, that trate limitations on the sustained band- removed from other installations, and the is 4,000 hours, we anticipate a typical width (< 32kbps) and on the data transfer direction towards the American tower will 80,000kWh, and consequently 20 tons of cost as well (just lower than above). On eventually be preferred. fuel per year to be transported, for this the other hand the BGan Inmarsat service instrument only. This would take a frac- is not fully supported at polar latitudes. Additional important work is to be carried tion of the summer traverses during ins- Furthermore an analysis of the scientific out before a final statement can be issued trument operation corresponding to 4% objectives shows that the construction of with respect to feasibility, especially with of the whole season capacity. This may a permanent high bandwidth data link at respect to the instruments that pose a increase to 18% of total capacity if the Concordia is mandatory. To this aim the major challenge, the large ones. After a de- maximum power is requested. USTP (Info-Telecommunication of PNRA) cision is taken with respect to which ins- proposes to carry on technical tests to truments will be eventually selected for Data transfer from the instrument to the validate the site with respect to satellite implementation, and which will be their Dome C main base, and from Dome C to communication feasibility starting with sequence of installation, detailed final the mainland appear different from one the Dome C 2009-2010 summer campaign. analysis of the actual characteristics of the instrument to the other. The small instru- To allow a simple hardware transportation equipment, and detailed flow charting of ments, like SIAMOIS, appear easy to accom- to Concordia and turn on the link soon the logistical steps for their transportation plish. ICE-T seems to need local storage of an antenna of 2.4m was chosen. Should to Dome C, for their physical installation data, due to the amount of data that are the test be positive the goal is to perform on site, and for the subsequent operation generated. The intermediate instrument a winterover test, through a non definitive of the individual instruments, will be re- requirements are not detailed. The large antenna radome. The facility is tailored quired before the duration of the whole instruments appear feasible, in the case of for a direct internet access with a starting operation can be assessed. .

The «raid» from Dumont d’Urville to Dome C.

71 Public outreach Public

72 Exhibition at the A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020). Aéroports de Paris in the IPY framework

6 Public outreach 6a Introduction

The fascination stronomy and Antarctica are two two tools as starting points: appealing words by themselves. • the ARENA leaflet, for astronomy and polar Astronomy in Antarctica is a fasci- • the ARENA public outreach website. Anating blend for which ARENA is attemp- research in the public ting to define a roadmap for future chal- ARENA has also taken advantage of two is strong. The recent lenging instruments and observations. major international events to present its In order to publicize its activities during activities, i.e., the International Polar Year International Polar Year the past four years and also in order to (2007-2009) and the International Year of (2007-2008) and prepare the public towards future activi- Astronomy (2009), as well as more local ties, the ARENA network has developed events in various locations in Europe. . International Year of Astronomy (2009) were major events that stimulated this public interest. ARENA 6b ARENA leaflet recommends that

the momentum created n order to describe the ARENA activi- The leaflet is now available in three lan- by these actions be ties to a large public (teachers, profes- guages: English, French and Italian. sional and amateur astronomers and maintained through Ialso the general public), a 4-page leaflet It can also be downloaded from regular popular events has been realized. It has been elaborated http://arena.unice.fr/IMG/pdf/ARENA_ to answer the following questions: leaflet_english.pdf. . presenting the most • Why is Antarctica appealing for astrono- recent results and mers? What is the ARENA network? Who achievements of polar are the ARENA partners and what are the objectives of this network? astronomy to the public. • What are the advantages for astronomers to observe from Dome C? • Where is Dome C and what does it look like? • What are the fundamental astrophysical questions that an observatory at Dome C can tackle? • What are the instrumental projects to answer these questions?

3,000 French and English copies have been released. They were sent to the 22 ARENA partners, outreach science centres and journalists. 1,000 leaflets were distributed during the ARENA opening ceremony of the International Year leaflet front page of Astronomy at UNESCO in January 2009. in english

73 .A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020)

6c ARENA public outreach website

here are numerous websites and The goal of the latter was and remains Antarctica does host an excellent site blogs about Antarctica, Concordia to reach and motivate the wide public for future astronomical ground based and about activities linked to Astro- and especially teachers and students of observatory in the 21st century, there is Tnomy in Antarctica. Extracting the informa- different level of education systems. The indeed an obligation of generating an tion of high value, synthesizing it by assem- main aim of this website is to present effective flow of information about the bling and selecting the best visual material the unique potentialities of Antarctica to contributions made to the European (images and videos) related to astronomy set up an astronomical observatory that knowledge and scientific excellence, and Antarctica was one of the priorities of will perform exceptional observations the value of collaboration on a Europe- the work done when the network started as well as to describe the scientific pro- wide scale, and the benefits to EU citi- to develop the ARENA public outreach grammes and instruments. Its content is zens in general. The website will strive at website (http://www.arena.ulg.ac.be/). in English and French. making this possible. .

http://www.arena.ulg.ac.be/ Public outreach Public

74 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

6d Recommendations Examples of exhibitions in the framework of the International Polar Year (Luxembourg Garden near the French Senate -up-, Musée des Arts et Métiers for future activities -down- in Paris)

he public outreach website ought Action 3 to continue being updated in the Develop a resource centre about Astro- near future. Beyond that, there nomy in Antarctica in forms of a portal Texists a clear need for coordination in including virtual press, public, scientific order to maximize the impacts of what rooms. Financial support provided by has been achieved in the present context government education ministries, natio- of ARENA. This is important in the frame nal or international funding agencies or of long term cooperation on Antarctic as- individual research institutions is highly tronomy at an international level. Several needed to develop further planning of actions can be thought of at this point in communications actions with full-time/ time, although they may appear a bit pre- professional communicators. mature as far as the present roadmap is concerned. For instance: What is clear nevertheless is that a considerable outreach effort will have to be Action 1 included in the next steps towards es- Develop a European level platform for com- tablishing an important astronomical munication and coordination amongst outpost in Antarctica. Such a project will education, outreach and communication indeed be comparable to major ground professionals with online forum to discuss based projects or programs such as VLT/ ideas in advance and meet on line to iden- VLTI, ALMA, E-ELT, to large space missions, tify interests and priorities. Create an expert such as HST, Planck, XMM, INTEGRAL, database with open source material Mars & Venus Express or to solar system exploration missions. In all these cases, a Action 2 considerable outreach programme has Establish a network which will actively fol- been set up and this must be taken as low-up the “Vision towards European Astro- example to be followed in the case of nomy in Antarctica” and a team to coordi- European Astronomy in Antarctica. One nate the inputs at the international level. must start preparing it as of now. .

75 Funding and manpower requirements and manpower Funding

76 Celebrating the set up A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020). of the IRAIT enclosure (summer campaign 2008-2009)

7 Funding and manpower requirements 7a Cost and funding

The Concordia station meaningful roadmap necessarily international agencies has to be set up. includes an estimate of the fun- National and possibly international agen- could become during ding and man power resources that cies should include the project in their Amust be raised and deployed to carry out own plans, simultaneously. the next decade a major its recommendations. Although these pro- platform for astronomical jections are still uncertain at this stage, par- The ARENA working groups were asked ticularly for the largest projects, we outline to draft a cost estimate of the different observations benefiting in this chapter the budget that the working phases of their projects over the next de- groups are requesting. We estimate that cade. These financial projections are only from unique atmospheric the injection of an overall amount of 50 to rough estimations and should become conditions. Europe 100 M€ during the next ten years is desira- more accurate as the industrial studies ble to start a significant European Obser- progress. The only mesoscale project for is in a foremost position vatory in Antarctica, including 5 to 6 small which a complete phase A study has instruments and a mesoscale facility. been fully achieved is PILOT, from which to be a world leader in this PLT is derived. challenging endeavour. Funding, implementing and running small projects of a few million euros is Tables 15 to 17 synthesize the status, cost We estimate that the feasible at the level of one country or la- estimates and possible dates of operations injection of 50 to 100 M€ boratory. They do not need a heavy and of the instruments documented by the sophisticated project management. For ARENA working groups. The cost of pro- during the next 10 years instance, ASTEP a project of less than jects that have not yet started a phase A 2 M€ (consolidated) is basically funded study are obviously very rough estimates. for the study and by France through INSU and ANR grants Figures 24 and 25 show projections of implementation and is managed at the level of the Fizeau the annual costs that would be required Laboratory, IRAIT, an instrument of com- by the projects proposed by the working of state-of-the-art parable cost, is basically supported by groups. They include consolidated phase the University of Perugia and the Italian A and B studies, and unconsolidated astronomical equipments agencies (INAF/PNRA) with some smal- construction costs. The consolidated costs is a prerequisite to give ler contributions from Spain (Granada, of construction will result from the phase Barcelona) and France (CEA). B studies. Figure 26 shows the relative the necessary impetus to costs of the different projects proposed by More ambitious projects exceeding an the working groups. a European Astronomical overall cost of 10 M€ (mesoscale projects) Observatory in Antarctica. such as PLT will require the creation of an From Fig. 24, it is immediately apparent international consortium able to raise the that if all these projects (PLT, ALADDIN, funding and manpower to carry out the AST) were to be developed in the next successive phases of the project from the decade, the peak of funding would oc- concept study to the routine operations cur by 2014-2018 and the total injection and data analysis. A consortium agree- of money into these projects would ex- ment between partners from different ceed 100 M€ during the decade, which countries with possible contributions of is likely to be unrealistic.

77 .A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020)

Besides, the polar agencies could obviously not cope with the simultaneous implementation of three major projects on the site in this decade. Therefore, to be realistic, the only mesoscale project that has a chance to be effectively implemented in the next ten years is PLT: the other ones will have to be shifted to the subsequent decade.

The overall budget needed to run the existing instruments, and to implement SIAMOIS and PLT, would add up to about 50 M€ in the decade (see Fig. 25) .

The main possible sources of funding Fig. 24 are the national agencies, the Euro- pean Commission through its Research Infrastructures Programme, mainly for design studies and other international organizations. For instance, the PLT team is aiming to submit a proposal for a phase B study. Although it is unlikely that ESO will contribute to the funding of projects in Antarctica in the coming years, we stress the fact that its support would give a strong impetus to European Antarctic Astronomy. .

Fig. 24: Cost projection for the next decade including all projects considered in the roadmap (overall cost 115 M€). The cost per year of each project corresponds to the height of the respective colour area. The profiles are preliminary estimation based on the information provided by the working groups.

Fig. 25: Cost projection for the next decade including PLT as the only meso scale instrument implemented Fig. 25 during the next decade.

Fig.26: Relative cost estimations of the projects proposed by the working groups over the next decade.

Fig. 26 Funding and manpower requirements and manpower Funding

78 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Table 15 Instruments currently under implementation at Dome C Instrument Present status Estimated Main sources of funding Start full opera- consolidated cost tion (estimated) ASTEP In commissioning ~2 M€ ANR, INSU 2010

IRAIT In commissioning ~2 M€ INAF, PNRA, CSIC, UGR, CEA 2011 COCHISE In operation ? PNRA, Università di Roma 2008 BRAIN/QUBIC In construction 3M€ + Logistics IN2P3, PNRA 2014

Table 16 Instruments in phase B Study Instrument Present status Estimated cost PhaseB/ Phase B status/possible Construction, possible Start full opera- construction source(s) of funding source(s) of funding tion (estimated) Ready for construction/ 100 k€/ ~2 M€ done/Observatoire de Paris INSU, ANR 2012 SIAMOIS seeking funds for implementation

ICE-T Ready for construction 180 k€/2.5 M€ done/AIP AIP 2016 4 M€/20 M€ Phase A done (PILOT), to be done/ EC, Including 1 focal instru Europe, Australia 2018-2020 PLT seeking funds for phase B study Australia ment and infrastructure

Table 17 Instruments in phase A or concept study

Instrument Present status Estimated Phase A, possible Phase B, possible source(s) Construction: possible Estimated date Overall cost source(s) of funding of funding source(s) of funding of operations and (2010-2020) running costs AST Concept study > 25 M€ CEA, INAF, Industries, FP7 > 2020

ALADDIN Concept study > 20 M€ EC, ESA? EC, ESA ? ? > 2020 ~ 8 M€ 2012-2013 Including ANR, FP7 Space (Sup- ANR, FP7 Space (Support 1 telescope France, Italy, Germany, Concept study 3 focal instru port of ASPIICS ESA of ASPIICS ESA PROBA-3) 2015-2016 AFSIIC Belgium and Russia ments and PROBA-3) FP7 Design Study Complete infrastructure 50 k€/year.

79 .A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020)

7b Personnel and training

ersonnel represents an important the number of well-trained staff. A clear Therefore, the implementation and ope- issue in the future development of separation must be made between dark ration of any instruments should be astronomical facilities in Antarctica. and bright time programmes. Although consistent with this manpower upper PThere is no doubt that the polar agencies a winterover at Dome C is an appealing limit. The construction of new service are able to manage the implementation experience, the number of candidates buildings at Concordia is unlikely to be of any reasonably large project at Dome C, having the required expertise is not un- undertaken in the period that this road- to deploy the appropriate means of limited and thus, if larger instruments map encompasses. conveyance and building resources and were to be installed, we would strongly to host adequately the necessary person- recommend broadening the call to apply Since the winterover staff are essentially nel during the construction phase. for winterover runs. dedicated to the functioning of the station, the number of “astronomers” staying However, the careful investigation made This call should not be limited to the during winter will be two, or at most three. by the ARENA activity NA4 ends up with Italian and French communities, but be In addition, only very limited outdoor the final conclusion that PLT (or PILOT) open to other countries in the framework activity is allowed in winter. For these is the only project fitting within the pre- of a trans-national access agreement that reasons, a high degree of automation and sent logistics capability. The other large the EC, for instance, could support throu- robotic operation of the telescopes and projects would necessarily require a si- gh its future 8th FP. Australia, which is instruments should be a major priority gnificant upgrade of the station capacity expected to be a major partner in astro- in their future design. Scientific program- and logistics that would result in a signi- nomical developments at Dome C in the ming of the facility should avoid any sort ficant extra cost. future, should be part of such a trans-na- of instrument configuration change over tional access agreement. The real cost of or maintenance during winter. As for the From the scientific personnel point of one person spending a winter at Dome C period of construction of buildings and view, the situation is more uncertain. Wor- should also be evaluated accurately to heavy structure in summer, this is essen- king in Antarctica, particularly in winter, be taken into account in the consolida- tially limited to three to four months a requires special skills and training. Excel- ted costs for future European proposals. year: consequently, any construction that lent physical and psychological condi- needs a year in “normal” conditions will tions for a life of several months in small In any case, the number of the winterover need three to four years at Dome C. group in complete isolation from the staff, which is currently about 15, is unli- world are an obvious prerequisite. The kely to increase significantly in the next Taking into account the delays imposed increasing number of instruments and ten years. This number is basically limi- by the shipping of heavy structures and the future installation of larger facilities ted by the hosting capacity of the station pieces of material to Dome C, and consi- would require a significant increase in (rooms, fuel and food provision…). dering the recent delays observed in setting up even small instruments, the construction of a mesoscale facility (PLT class) will not be less than five years. Day- time instruments (such as solar, radio and thermal infrared waves) may have a different status. To take advantage of the much more comfortable operating conditions in summer, we strongly recommend that PLT be also operated in bright time in the appropriate spectral range (beyond 3µm).

The proper management of the construction and planning is per se a major task that should be thoroughly considered in any phase B study. Polar Agency expertise and good communication with their operational staff will be extremely important during this phase. . Funding and manpower requirements and manpower Funding

80 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

81 Synthesis of the roadmap and final recommendations of and final the roadmap Synthesis

82 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

8 Synthesis of the roadmap and final recommendations

The following statements Statement 1 Concordia to teams that contribute to On the overall interest of Antarctica the assessment of the site, to the resulting have been endorsed conditions to the development databases as well as to provide a free of European astronomy and astrophysics access to these data on as short a time- by the CMC following Considering the exceptional atmospheric scale as possible after they have been the 3rd ARENA Conference conditions prevailing at Dome C, the collected. A dedicated entity should be ARENA consortium strongly supports in charge of maintaining these data ba- held in Frascati in May the creation of a European/international ses after the end of ARENA. In addition, astronomical facility on the Antarctic the ARENA consortium strongly recom- 2009. They are translated Plateau, building upon the successful mends that ESO be involved in the future hereafter into ARENA establishment of Concordia station by site testing at Dome C. France and Italy. recommendations Statement 5 so that as of January 2010 Statement 2 On the most promising science cases On the medium-and long-term objective The ARENA consortium commends the the necessary studies of the ARENA roadmap science cases proposed by the working The ARENA consortium strongly encou- groups and described in statement 9, be initiated and rages international cooperation in An- herebelow. undertaken in order tarctica, in particular with respect to the establishment of large observing astro- Statement 6 to enable the “European nomical facilities at Dome C (or possibly On the instrumental polar constraints. elsewhere on the Antarctic plateau if ano- State of the art R&D. International Observatory in Antartica” ther even better site were to be discove- pooling of expertises. project. red). The ARENA roadmap will serve as a The ARENA CMC recommends that ap- guideline to the national and international propriate R&D studies specific to the agencies and the European Commission Antarctic constraints be made in ad- for the developments of these facilities in vance of any decision to implement a the coming decade (2010-2020). meso-scale facility. Among them are, frost mitigation, specific ground layer adaptive Statement 3 optics (GLAO), 20-30m tower construc- On the size of projects tion. The CMC strongly recommends that The ARENA consortium strongly sup- a simple GLAO system be implemented ports the need of meso-scale facilities to and assessed in the polar environment be developed. Nevertheless it also sup- e.g., using already installed telescopes ports small experiments as site testers such as IRAIT. In addition, design studies, and pathfinders. design and model building of highly stiff towers able to support different types of Statement 4 instruments (solar or night telescopes) On the present status of site assessment are strongly encouraged. The CMC fur- and recommendations in the future ther recommends to foster a politics of The ARENA CMC strongly emphasizes the pooling of the polar expertises acquired need to widely open access to the site of by the different teams.

83 .A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020)

Statement 7 WG3 - Optical/IR interferometry phase A study for a high resolution ima- On the need to upgrade logistics ALADDIN is the most advanced project ging and spectroscopy facility with coro- The ARENA CMC strongly recommends for interferometry at Dome C (concept nal capabilities, first, of 1.4m equivalent improvements of the following issues: studies made by an industrial team). It is diameter (3x0.5m off-axis). • Alternative clean energy production. thus recommended for a more detailed New larger astronomical facilities will phase A study. A stronger support from The instrumentation would enable 2D require a significant improvement of the interferometry community should be spectro-imaging, spectropolarimetry, ma- electric power production, preferably obtained. Alternative projects of pathfin- gnetoseismology and direct magnetic avoiding atmospheric pollution of the ders toward a European kilometric array field measurements in the chromosphere site by aerosols that would degrade the interferometer are also to be investigated and corona. The proponents must howe- unique sky properties. in parallel. We recommend to measure ver demonstrate on a temperate site that • Increase drastically the communication and monitor relevant atmospheric pa- the required interferometric technique is bandwidth. Fast and wide band interac- rameters (turbulence profile, isopistonic feasible for such instruments. . tion with “the rest of the world” is essential angle, coherence time, outer scale). to carry out a project and to treat interacti- vely huge amounts of data. It constitutes an WG4 - Long time-series photometric essential advantage over space missions. observations The CMC endorses the recommenda- Statement 8 tions made by the WG4, which essential- On seeking for funding ly supports 4 small projects presently in and relationship with agencies different phases of implementation and The ARENA CMC recommends that fur- the PLT project. ther funding be sought from the EC and • IRAIT is a milestone of ARENA (being (inter-) national agencies to continue its part of its workprogramme). It should be coordination activities. The necessary set up rapidly and made operational this efforts should be made to include the next summer season (2009-2010), for first Concordia station in the ESFRI roadmap light in winter 2010. in order that its scientific research equi- • ASTEP received its first light at Dome C pments be implemented rapidly. A peer in November 2009. It should rapidly pro- reviewing process by the ESF units may vide scientific data (2010-2011) and thus help on this issue. be strongly supported by the relevant agencies. Statement 9 • ICE-T is graded the top priority ins- On the projects presented by the working trument for time-series photometry at groups and their endorsement by the Dome C and the CMC recommends that ARENA CMC an agreement be made with the French From statements to recommendations: and Italian polar agencies to host this ins- the following paragraphs aim at extrac- trument at Concordia. ting the quintessence from the 6 wor- • SIAMOIS is graded the top priority dedi- king group reports in order to convert cated instrument for advanced time-series the statements above into ARENA re- spectroscopy at Dome C. commendations. WG5 - Cosmic Microwave Background WG1 - Wide-field optical IR astronomy Antarctica offers exceptional conditions PLT (Polar Large Telescope) is the most for CMB research due to its cold and dry mature project in the mesoscale category. climate. Dome C offers particular advan- The Phase A worked out by the Austra- tages, relative to South Pole, for the accu- lians in 2007-2008 for PILOT should serve rate measurement of the CMB B-mode as a robust basis for further PLT studies. polarization, one of the major goals of This project is also supported by WG4 cosmology in the coming years. The ARE- for a phase B study (ending by 2013). NA CMC strongly supports efforts to esta- The PLT facility should be able to enter blish CMB experiments at Dome C and into a construction phase by 2014 and in particular the international QUBIC start being implemented in 2015-2017 at project whose bolometric interferome- Dome C, with a first light by 2018. ter will combine the sensitivity of bolometric detectors with the optical acuity WG2 - Submillimetre-wave astronomy of interferometers. The ARENA CMC also First publicly The ARENA CMC recognizes the exceptio- supports efforts to further explore syner- released image nal interest in the project, which proposes a gies between the CMB projects and the from VISTA, the world’s large telescope facility highly complemen- 25m AST project. largest survey telescope, showing the spectacular tary to the Herschel space observatory and star-forming region to ALMA, in a site which seems to provide WG6 - Solar astrophysics known as the Flame much better conditions in the THz domain Solar astrophysics could take considera- Nebula, or NGC 2024, than any site in Chile. AST (Antarctic Sub- ble advantage of the exceptional seeing in the constellation millimetre Telescope) is thus recommen- conditions regularly recorded in summer of Orion (the Hunter)

Synthesis of the roadmap and final recommendations of and final the roadmap Synthesis ded for a rapid phase A study. time at Dome C. The CMC recommends a and its surroundings. 84 A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

85 86 Annexes A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Annexes Aa Contributors to the ARENA roadmap

Consortium Management Committee and Networking Activity leaders

Carlos Abia CMC full member Universidad de Granada Spain Jarle Brinchmann CMC full member Universidade do Porto* Portugal Maurizio Candidi NA4 leader INAF, Rome Italy Nicolas Epchtein Coordinator, CMC chair CNRS - Fizeau, Nice France Eric Fossat Scientific Advisory Board chair CNRS - Fizeau, Nice France Yves Frenot CMC (invited) IPEV, Brest France Roland Gredel NA2 leader MPIA, Heidelberg Germany Thomas Henning CMC full member MPIA, Heidelberg Germany Gérard Jugie CMC (invited) IPEV, Brest France Mark McCaughrean CMC full member University of Exeter** United Kingdom Vincent Minier CMC full member IRFU/CEA, Saclay France François Pajot CMC (invited) IAS, Orsay France Marie-Laure Péronne CMC (invited), Project manager CNRS - Fizeau, Nice France Paolo Persi CMC full member INAF, Rome Italy Luigi Spinoglio CMC full member INAF, Rome Italy John Storey CMC (invited) UNSW, Sydney Australia Jean-Pierre Swings CMC full member, NA3 leader Université de Liège Belgium Aziz Ziad NA2 co-leader CNRS - Fizeau, Nice France Hans Zinnecker NA5 leader AIP, Potsdam Germany

*Now at Leiden Observatory, The Netherlands **Now at ESA-ESTEC, Noordwijk,The Netherlands

87 88 Annexes . A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) Gianpietro Marchiori Carsten Kramer Frank Israel Yves Frenot Gilles Durand Emmanuele Daddi Michel Apers Oscar Straniero Paolo Persi Jean-Pierre Maillard Nicolas Epchtein Carlos Eiroa Maurizio Busso Michael Burton Denis Burgarella Andrew Bunker Michael Andersen Luca Valenziano Pascal Tremblin Nick Tothill Luigi Spinoglio Nicola Schneider Lucia Sabbatini Marco de Petris Miroslav Pantaleev Luca Olmi Vincent Minier - LAM,- Marseille, France), Nice, France), (Anglo-AustralianObservatory, Epping, Australia), WG1 -Wide-fieldopticalandinfraredastronomy Working Groups WG2 -Submillimetre-waveastronomy butions totheWG1roadmap. and (UNSW, Storey Sydney, Australia), Australia),Sydney, Lyon, France), de Observatoire CRAL, - (CNRS Prugniel Langlois Maud Paris, France), de (Observatoire IAP,Paris, France), (Anglo-AustralianObservatory, Epping, Australia), (RAMS-CON, Germany), acknowledges WG1 CR - Fizeau, Nice, France), - (CNRS (CNRS - CRAL,Vauglin- Isabelle Lyon,(CNRS de Observatoire France) Co-chair Denis Fappani Chair Co-chair Co-chair (CNRS - CRAL, Observatoire de Lyon,de France),CRAL,Observatoire - (CNRS

Tim Bedding Tim (CNRS - Fizeau,Nice,- France), (CNRS Schmider François-Xavier CR - ieu Nc, France), Nice, Fizeau, - (CNRS Abe Lyu Michael Ashley (UNSW, Sydney, Australia), (UNSW, Lawrence Jon Sydney, Australia), INAF, Bologna IRFU/CEA, Saclay University ofExeter INAF, Rome IRFU/CEA, Saclay Università degliStudiRoma Tre INAF, Rome Onsala Observatory INAF, IRFU/CEA, Saclay EIE, Mestre Cologne/KOSMA Leiden Observatory IPEV, Brest IRFU/CEA, Saclay IRFU/CEA, Saclay Thales Alenia Space, Toulouse INAF,Teramo INAF,Rome -IAP,CNRS Paris CNRS -Fizeau, Nice UNAM, Madrid Universita degliStudidiPerugia UNSW,Sydney CNRS -LAM, Marseille University ofOxford AIP, Potsdam (SESO, Aix-en-Provence, France), Arcetri, Florence (UNAM, Spain), Madrid, Mora Alcione Nick TothillExeter,(Universityof Nick Kingdom) United (UNSW,Sydney, Australia), CR - A, asil, France), Marseille, LAM, - (CNRS Roux Le Brice (CNRS - (CNRS Beaulieu Jean-Philippe (CNRS - Fizeau,- (CNRS Carbillet Marcel (UNSW, Saunders Will Joss Bland-Hawthorn Bland-Hawthorn Joss Marc (CNRS Ferrari ofag Ansorge Wolfgang Djamel Mékarnia Djamel Thibaut Le Bertre Le Thibaut Italy Italy France France Spain Italy Australia France United Kingdom Germany Italy France United Kingdom Italy France Italy Italy Sweden Italy France Italy Germany The Netherlands France France France France Jeremy Jeremy Bailey for their contri- their for Philippe John

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

WG3 - Optical and infrared interferometry

Olivier Absil Université de Liège Belgium Marc Barillot Thales Alenia Space, Cannes France Vincent Coudé du Foresto Observatoire de Paris France Chair Carlos Eiroa UAM, Madrid Spain Emmanuel di Folco Observatoire de Genève Switzerland Yves Frenot IPEV, Brest France Thomas Herbst MPIA, Heidelberg Germany Claude Jamar AMOS, Liège Belgium Jean Surdej Co-chair Université de Liège Belgium Farrokh Vakili CNRS - Fizeau - OCA, Nice France

WG3 acknowledges Xavier Daudigeos (Observatoire de Paris, France) and Denis Defrère (Université de Liège, Belgium) for their contributions to the WG3 roadmap.

WG4 - Long time-series photometric observations

Jean-Philippe Beaulieu CNRS - IAP, Paris France Giuseppe Cutispoto INAF, Catania Italy Hans Deeg Co-chair IAC, Tenerife Spain Eric Fossat CNRS - Fizeau, Nice France Tristan Guillot CNRS - Cassiopée - OCA, Nice France Benoît Mosser Observatoire de Paris France Heike Rauer Chair DLR, Berlin Germany Klaus Strassmeier AIP, Potsdam Germany

WG5 - Cosmic Microwave Background

Grupo de Radioastronomia, Instituto Portugal Domingos Barbosa de Telecommunicações, Pólo de Aveiro Paolo de Bernardis Chair Università di Roma, La Sapienza Italy François-Xavier Désert CNRS - LAOG, Grenoble France Massimo Gervasi INAF, Milan, Bicocca Italy Yannick Giraud-Héraud CNRS - APC, Paris 7 France Co-chair Ernst Kreysa Max Planck Institut Radioastronomie, Bonn Germany Bruno Maffei BO Manchester United Kingdom Silvia Masi Università di Roma La Sapienza Italy Philip Mauskopf University of Cardiff United Kingdom François Pajot CNRS - IAS Orsay France Luca Valenziano INAF, Bologna Italy Licia Verde ICE IEEC/CSIC, Barcelone Spain

89 90 Annexes . The 22 ARENA partners The 22ARENA Thalès AleniaSpace (TAS) European Southern Observatory(ESO) Centro deAstrofisicadaUniversidade doPorto(CAUP) Société EuropéennedesSystèmesOptiques (SESO) Advanced MechanicalandOpticalSystems (AMOS) SHAKTIWARE (SHAK) University ofNewSouthWales (UNSW) Programma NazionalediRicercheinAntartide(PNRA) Université deLiège(ULG) Commissariat àl’EnergieAtomique(CEA) Observatoire deParis(OP) Deutsches ZentrumfürLuft-undRaumfahrt(DLR) Institut Paul-EmileVictor (IPEV) Università degliStudidiPerugia(UNIPG) University ofExeter(UNEXE) Instituto deAstrofísicaCanarias(IAC) Consejo SuperiordeInvestigacionesCientíficas(CSIC) Universidad deGranada(UGR) Astrophysikalisches Institut(AIP) Max PlanckInstitutfürAstronomie(MPIA) Istituto NazionalediAstrofisica(INAF) Centre NationaldelaRechercheScientifique(CNRS) Institution A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020) Jean Vernin Maria DoloresSanchezSierra Anna Pospiezsalska-Surdej Khaled BenAbdallah Cyrille Baudouin Martine Adrian-Scotto André Preumont Jean-Marie Malherbe Philippe Lamy Sergey Kuzin Serge Koutchmy Jean-Laurent Dournaux Carsten Denker Luc Damé Vincenzo Andretta Jean-Philippe Amans Contact point(s) Michel Apers Jorge Melnick Leibundgut -GuyMonnet -Bruno Jarle Brinchmann Denis Fappani Jean-Pierre Chisogne Didier Rabaud John Storey Antonio Cuccinotta-Chiara Montanari Jean-Pierre Swings Pierre-Olivier Lagage Slimane Bensammar Heike Rauer Gérard Jugie- Yves Frenot Busso Maurizio Mark McCaughrean Eduardo Martin Jordi Isern Carlos Abia Klaus Strassmeier -HansZinnecker Thomas Henning Luigi Spinoglio Nicolas Epchtein Other contributors Other contributors data at DomeC. WG6 acknowledges WG6 -Solarastrophysics Chair NA2 leader(2006-2007) Communication (2008-2009) Co-chair Eric Aristidi and Web Programming (2007-2008) Communication (2006) Communication (2008-2009) Université Libre deBruxelles Observatoire deParis, Meudon CNRS -LAM, Marseille Lebedev Institute, Moscow CNRS -IAP, Paris Observatoire deParis, Meudon AIP, Potsdam Verrières-le Buisson d’Aéronomie,CNRS -Service INAF,Naples Observatoire deParis, Meudon Web Programming (2006) Eric Fossat for their help to access to the summer Town Toulouse Garching-bei-München Porto Aix-en-Provence Liège Marseille Sydney Rome Liège Saclay Paris Berlin Brest Perugia Exeter Tenerife Barcelona Granada Potsdam Heidelberg Rome Nice CNRS - Fizeau, Nice CNRS -LUAN, Nice CNRS - Fizeau, Nice CNRS -LUAN, Nice Université deLiège CNRS - Fizeau, Nice Belgium France France Russia France France Germany France Italy France Country France Germany Portugal France Belgium France Australia Italy Belgium France France Germany France Italy United Kingdom Spain Spain Spain Germany Germany Italy France France France Belgium France France France A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

Ab List of instruments at Dome C past, in operation, or being set up in 2009

Site testing

Meteorology Turbulence AWS SUMMIT DIMM (Since 1980): Automatic Weather Station (Summer 2003-2004, winter 2008-2009): (Summer since 2000, winter since 2005): measuring ground level pressure, tempe- submillimetre tipper measuring opacity Differential Image Motion Monitor measu- rature, humidity, wind speed and direction. and emission at 200 and 350µm. ring integrated seeing close to surface. Meteo balloons PAERI GSM (Summer since 1995, winter since 2005): (Summer 2002-2003 and 2003-2004): in- (Since 2006): Generalized Seeing Monitor measuring profile of temperature, pressure, frared FTS measured sky emission and measuring outer scale, seeing and isopla- humidity, wind speed and direction. opacity from 3-20µm. natic angle at ground level. COBBER Nigel MOSP (Winter 2003-2004): low power mid-infra- (Summer 2004-2005): fibre-coupled opti- (Since 2008): Monitor of Outer Scale Profile. red thermopile detector measured cloud cal spectrometer measured sky spectral SSS cover statistics. emission. (Since 2005): Single Star Scidar: Monito- 2 ICECAM Gattini ring of Cn profile. (Winter 2002-2003): autonomous self-powe- SBC (since winter 2006): narrow field op- SODAR red visible CCD camera measured cloud tical camera to measure sky background (Summer/winter 2003‑2004): commercial cover statistics. in the visible. acoustic radar measured turbulence wi- Vaisala sIRAIT thin the 30-900m surface layer. FD12 (Summer 2004): visibility sensor (Since 2006): a 0.25m optical telescope for MASS measured precipitation rates. asteroseismology and site qualification. (Winter 2004): Multi-Aperture Scintilla- Gattini PAIX tion Sensor measured turbulence profile All sky (Winter since 2006): wide-field op- (Since winter 2007): photometer desi- of atmosphere from 0.5-22km. tical camera to measure cloud cover and gned for measurement of the optical at- Microthermal balloon auroral distribution. mospheric extinction. (Winter 2005): temperature sensors measu- STABLEDC COCHISE ring the atmospheric turbulence profile. (2004-2005): an array of instruments (Since winter 2008): a 2.6m diameter Microthermal mast measuring the thermal structure in the millimetre-wave telescope designed for (Winter 2005-2006): tower mounted mi- boundary layer. cosmological science but should also crothermal sensors measuring the turbu- measure atmospheric opacity. GIVRE lence in the 0-30m surface layer. (Winter since 2007): an experiment to TAVERN-SP Sonics measure frost and ice accumulation on (Planned for winter 2010): a small opti- (Since 2006) measuring temperature and exposed surfaces. cal telescope designed to measure aero- wind speed components in the surface sol densities. layer from ultrasound emission, and de- Sky emission and opacity 2 ASTEP rive Cn profile through a model. Solar hydrometer (Since 2008): a 0.42m optical telescope (Summer 1996-1997, 2007): measured pre- designed for exoplanet detection and cipitable water vapour. photometric site characterisation. APACHE96 IRAIT (Summer 1996-1997): 0.6m millimetre- (Planned for winter 2010): a 0.8m near- wave telescope measured atmospheric and mid-infrared telescope to be equipped stability and sky noise. with the AMICA instrument with science priorities but site qualification capabilities.

91 92 Annexes A . Ac Automatic Weather Station AWS Alfred Wegener Polar Institute(German Agency) AWI Advanced Technology Solar Telescope ATST Advanced Telescope Project ATP ERA-NET for Astronomy and Astrophysics ASTRONET and RemoteObservatory Antarctic Submillimetre Telescopes AST/RO Antarctic Submillimetre Telescope AST et l’InterférométriedelaCouronne Solaire Association deSatellites Pour l’Imagerie ASPIICS for Astrophysics Antarctic Research, aEuropean Network ARENA Atacama Pathfinder Experiment APEX (French National Research Agency) Agence Nationale pourlaRecherche ANR Antarctic Mid-Infrared CAmera (for IRAIT) AMICA Antarctic Detector MuonandNeutrino Array AMANDA Atacama Large Millimetric Array ALMA Demonstrator for Interferometric Nulling Antarctic L-band Astrophysics Discovery ALADDIN Astrophysikalisches InstitütPotsdam, Germany AIP Imaging andCoronagraphy Antarctica Facility for SolarInterferometric AFSIIC Antarctica 4mInterferometer A-FOURMI Australian Antarctic Division AAD for Observatory Antarctica Automated Astrophysical AASTO International Observatory Automated Astrophysical Site Testing AASTINO Anglo-Australian Observatory AAO from Antarctica (aSCARinitiative) Astronomy and Astrophysics AAA (tripleA) A Vision for European Astronomy andAstrophysicsthe Antarctic at station Concordia, DomeC(2010‑2020)

List of abbreviations

E D C B European Engineering Industrial EIE European Commission EC Deutsches Zentrum für Luft- und Raumfahrt DLR Differential Image MotionMonitor DIMM DEep NearInfraredSkySurvey Southern DENIS Degree Angular ScaleInterferometer DASI Centre deRecherche Astrophysique deLyon CRAL High-sensitivity for Source Instruments Extraction Cosmological Observations at Concordia with COCHISE Anisotropy Experiment Cosmic Background Radiation COBRA Centre National delaRecherche Scientifique CNRS Coronal MassEjections CMEs (ARENA executive committee) Management Committee Consortium CMC Cosmic Microwave Background CMB Canada-France-Hawaii Telescope CFHT Committee for Environmental Protection CEP Comprehensive Environmental Evaluation CEE Commissariat àl’Energie Atomique CEA Caltech Cornell Atacama Telescope CCAT Background RAdiation INterferometer BRAIN Extragalactic Radiations andGeomagnetics Balloon Observations ofMillimetric BOOMERanG Background LimitedInfrared Photometry BLIP of CosmicExtragalactic Polarization Background Imaging BICEP British Antarctic Survey BAS

F-GH I FP6/7 Field Of View FOV European Telescope Strategy Review Committee ETSRC Observatory European Southern ESO European Space Agency ESA on Research Infrastructures European Strategy Forum ESFRI European Project forin IceCoring Antarctica EPICA Emission Millimétrique EMILIE European -Extremely Large Telescope E-ELT Institut d’Astrophysique deParis IAP International Geophysical Year (1957-1958) IGY Initial Environmental Evaluation IEE International CouncilofScientificUnions ICSU The InternationalConcordia Explorer Telescope ICE-T International Astronomical Union IAU et deGéophysique deLiège Institut d’Astrophysique IAGL Hubble Space Telescope HST Hungarian-made Automated Telescope network HATnet Generalised SeeingMonitor GSM Global Oscillation Network Group GONG Ground Layer Adaptive Optics GLAO Ground-based European NullingExperiment GENIE Galactic Bulge GB Fourier Transform Spectrometer FTS (of theEuropean Commission) Sixth/Seventh Framework Programme

A Vision for European Astronomy and Astrophysics at the Antarctic station Concordia, Dome C (2010‑2020).

IN2P3 NCRIS SODAR Institut National de Physique Nucléaire National Collaborative Research SOnic Detection And Ranging et de Physique des Particules Infrastructure Strategy (Australia) SOFIA (French Research Agency) NSF Stratospheric Observatory For Infrared INAF National Science Foundation (US) Astronomy Istituto Nazionale di Astrofisica SOHO O - P (Italian Research Agency) SOlar Heliospheric Observatory INSU OASI Infrared and Sub-mm Antarctic Observatory SPICA Institut National des Sciences de l’Univers Space Infrared Telescope for Cosmology and (French Research Agency) OPTICON Astrophysics INFN Optical Infrared Coordination Network for Astronomy (an EC FP7 initiative) SPIREX Istituto Nazionale di Fisica Nucleare South Pole Infrared Explorer (Italian Research Agency) OGLE Optical Gravitational Lensing Experiment SPOT IPEV South Polar Optical Telescope Institut Paul Emile Victor (French Polar Agency) PAERI Polar Atmospheric Emitted SSS IPY Single Star Scidar International Polar Year (2008-2009) Radiance Interferometer PAIX STABLEDC IRAIT Study of the STABLE boundary layer at Dome C International Robotic Antarctic Infrared Telescope Photometer AntarctIc eXtinction PILOT SUMMIT ISO Sub-millimeter tipper Infrared Space Observatory Pathfinder for an International Large Optical Telescope SZE IYA 2009 Sunyaev-Zel’dovich Effect International Year of Astronomy (2009) PISNe Pair Instability Supernovae INSCAF T - U International Network for Scientific PLT TGL Cosmological Analysis of Foregrounds Polar Large Telescope Turbulent Ground Layer PNRA J - K - L TMT Programma Nazionale di Ricerche in Antar- Thirty Meter Telescope JACARA tide (Italian National Programme for Research Joint Australian Centre for Astrophysical in Antarctica) UGR Research in Antarctica Universidad de Granada, Spain PWV JWST Precipitable Water Vapour UNS James Webb Space Telescope Université de Nice Sophia Antipolis Q - R KEOPS UNSW Kiloparsec Explorer for Optical Planet Search QUBIC University of New South Wales Quasi Optical Bolometric Interferometry (Sydney, Australia) LAM RAMS-CON Laboratoire d’Astrophysique de Marseille V RAMS-CON Management Consultants LBT VISTA Large Binocular Telescope (Interferometer) S Visible and Infrared Survey Telescope LMC SBM for Astronomy Large Magellanic Cloud Sky Brightness Monitor VLBI LUAN SCAR Very Large Base Interferometry Laboratoire Universitaire d’Astrophysique Scientific Committee on Antarctic Research VLT(I) de Nice (now Laboratoire H. Fizeau) SDM Very Large Telescope (Interferometer) Subtractive Double Monochromator M - N W MCAO SDSS WIMP Multi Conjugate Adaptive Optics Sloan Digital Sky Survey Weakly Interacting Massive Particles MOLIERE SIAMOIS WISE Microwave Observation Seismic Interferometer Aiming to Measure Wide-field Infrared Survey Explorer Oscillations in the Interior of Stars LIne Estimation and REtrieval WMAP MOSP SMC Wilkinson Microwave Anisotropy Probe Monitor of Outer Scale Profile Small Magellanic Cloud 2 MPIA SNIa Max Planck Institut für Astronomie, Supernova of type 1A 2MASS Heidelberg, Germany SNe Two-Micron Sky Survey Supernovae

93 Acknowledgements

94 Acknowledgements

he ARENA consortium members are indebted to the European Commission for the funding of this coordination action of networking under grant RICA 026150 of the Sixth TFramework Programme.

Dr. Elena Righi-Steele is warmly thanked for her helpful contribution to the project as Project Officer and Prof. Gerry Gilmore for his participation in the project evaluation at the Mid Term Review on October 22, 2007 in Brussels.

We are grateful to the administrative personnel of the CNRS Délé- gation Régionale Côte d’Azur (DR20) in Sophia Antipolis and of the Hippolyte Fizeau Laboratory in Nice for their assiduous attention to the contract management.

The site assessment and the first astronomical experiments at Dome C would not have been possible without the full dedication of the staff of the French and Italian polar institutes at Concordia. We particularly acknowledge the research, technical and service teams that contributed to the success of the winterover campaigns (2005-2009). .

References

Giard M., Casoli F., Paletou F. (eds.), 2005, Proc. Conference on « Dome C Astronomy and Astrophysics Meeting » (Toulouse, June 28-30, 2004), EDP, EAS Publications Series, vol. 14. Epchtein N., Candidi, M., (eds.) 2007, Proc. 1st ARENA Conference on «Large Astronomical Infrastructures at Concordia, prospects and constraints for Antarctic Optical/IR Astronomy» (Roscoff, October 16-19, 2006), EDP, EAS Publications Series, vol. 25. Zinnecker H., Epchtein N., Rauer H., (eds.), 2008, Proc. 2nd ARENA Conference on «The Astrophysical Science Cases at Dome C» (Potsdam, September 17-2, 2007), EDP, EAS Publications Series, vol. 33. Spinoglio L. , Epchtein N. (eds.), 2010, Proc. 3rd ARENA Conference on «An astronomical Observatory at Concordia (Antarctica) for the next decade» (Frascati, May 11-15, 2009), EDP, EAS Publications Series, vol. 40. Burton M. (ed.), 2010, Proc. Special Session 3, XXVIIth IAU General Assembly, «Astronomy in Antarctica» (Rio de Janeiro, August 6-7, 2009), Highlights of Astronomy, vol. 15. .

95 Photograph credits Editor Editorial conception Olivier Absil: p. 46-47; Abdelkrim Agabi: p. 28, 50-51, 68, 81; Stefania Argentini: p. 31; ARENA Coordinator ARENA Project manager Eric Aristidi: Cover, p. 5, 14, 18, 23, 24, 26, 27, 31, 51, 69, 71, 88, 89; Rainer Arlt: p. 23; Nicolas Epchtein Marie-Laure Péronne Paolo de Bernardis: p. 16, 60; Erick Bondoux: p. 1, 14, 30, 42-43, 70, 91, 92-93; Runa [email protected] [email protected] Briguglio: p. 79; Michael G. Burton : p. 17; Zalpha Challita: p. 2; Chinese Centre for Antarctic Astronomy: p. 18; Courtesy Hinode: p. 63; Guillaume Dargaud: p. 62-63; Graphic conception Claude Delhaye: p. 6, 11, 18, 33, 86, 96; Gilles Durand: p. 69, 76; ESO: p. 34, 35, 55, 82, NovaTerra/ Delphine Bonnet 85; Yan Fanteï-Caujolle: p. 53; Gérard Grec: p. 16; Djamel Mékarnia: p. 36-37, 80, 90; http://www.novaterra.fr Axel Mellinger: p. 61; Benoît Mosser: p. 54; Hideaki Motoyama: p. 18; NASA: p. 41; François Pajot: p. 16; Marie-Laure Péronne: p. 72, 75; PNRA: p. 18; Cyprien Pouzenc: Photogravure p. 41; Lucia Sabbatini: p. 94; Göran Scharmer: p. 67; US Navy: p. 15; Jean Vernin: Noir.Ebene p. 18; Andrew V. Williams: p. 17; Friedrich Wöger: p. 63; Jonathan Zaccaria: p. 14. Printer Maps Pure Impression Produced by the Australian Antarctic Data Centre Stations as listed at http://www. «Print Environnement» comnap.aq/facilities (September 2009) - Map Catalogue N° 13698. certifié Iso14001

Concordia station (Dome C, Antarctica)

ARENA - Antarctic Research, a European Network for Astrophysics

Address Laboratoire Hippolyte Fizeau UMR 6525 (UNSA/CNRS/OCA) Université de Nice Sophia Antipolis (Faculté des Sciences) Centre National de la Recherche Scientifique Observatoire de la Côte d’Azur 28 avenue Valrose (Parc Valrose) 06108 Nice cedex 2 - France

Websites ARENA Portal: http://arena.unice.fr/ ARENA Public outreach: http://www.arena.ulg.ac.be/

Tel. +33 (0)4 92 07 63 22 Fax +33 (0)4 92 07 63 21