DOCSLIB.ORG

REPO RT SFROMOBSE RV ERSA Study of the Activity of G and K

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
REPO RT SFROMOBSE RV ERSA Study of the Activity of G and K R E P O RT S F R O M O B S E RV E R S A Study of the Activity of G and K Giants Through Their Precise Radial Velocity; Breaking the 10-m/sec Accuracy with FEROS J. SETIAWAN 1, L. PASQUINI 2, L. DA SILVA3, A. HATZES4, O. VON DER LÜHE1, A. KAUFER2, L. GIRARDI 5, R. DE LA REZA3, J.R. DE MEDEIROS6 1Kiepenheuer-Institut für Sonnenphysik, Freiburg (Breisgau), Germany; 2European Southern Observatory 3Observatorio Nacional, Rio de Janeiro, Brazil; 4Thüringer Landessternwarte Tautenburg, Tautenburg, Germany 5Dipartimento di Astronomia, Università di Padova, Padova, Italy 6Universidade Federal do Rio Grande do Norte, Natal, Brazil 1. Scientific Background giant stars and their progenitors. In par- ible stellar surface (as a result of stellar ticular, when combining accurate dis- rotation), they will also induce variabili- Asteroseismology is an indispensa- tances (e.g. from HIPPARCOS), the ty in the core of deep lines, as the Ca II ble tool that uses the properties of stel- spectroscopic determination of the H and K, which are formed in the chro- lar oscillations to probe the internal chemical composition and gravity along mosphere (see e.g. Pasquini et al. structure of stars. This can provide a di- with the oscillation spectrum, the stellar 1988, Pasquini 1992). Since FEROS rect test of stellar structure and evolu- evolutionary models will be required to allows the simultaneous recording of tion theory. Precise stellar radial veloc- fit all these observations. This could the most relevant chromospheric lines, ity (RV) measurements made in recent provide an unprecedented test bench it will be possible to test directly from years have not only discovered the first for the theories of the stellar evolution. our spectra the rotational modulation extra-solar planets, but have also un- Before this can be done, however, one hypothesis. In Figure 1, CaII K line covered new classes of low-amplitude must derive the full oscillation spectrum spectra of one target star taken at dif- variable stars. One such is represented (periods and amplitudes) for a signifi- ferent epochs are over-imposed: no ev- by the K giant stars which exhibit RV cant number of giant stars. idence for strong variability in the line variations with amplitudes in the range Although the short-period variations core is detected. of 50–300 m/s (Walker et al. 1989, in giants can only arise from radial and The expected rotational periods for Hatzes & Cochran 1993,1994 ab). This non-radial pulsation, the nature of the some giants are consistent with the ob- variability is multi-periodic and occur- long-period RV variations is still open to served periods and some evidence for ring on two time- scales: less than 10 debate. Possibilities include planetary equivalent-width variations of activity days and several hundreds of days. companions, rotational modulation by indicators accompanying the RV varia- In the most detailed study of a K gi- surface structure, or non-radial pulsa- tions have been found in two K giants ant star, Merline (1996) found 10 pulsa- tion. Each of these hypotheses has a (Larson et al. 1993; Lambert 1987). If tion modes with periods ranging from high astrophysical impact, and there the RV variations were caused by sur- 2–10 days in Arcturus. These modes are strong arguments to support each face inhomogeneities, then these were equally spaced in frequency, the of them. would be large enough to be resolved characteristic signature of p-mode os- When surface structures, such as ac- by future ground-based interferometry. cillations analogous to the solar 5- tive regions and spots, move on the vis- These stars will thus make excellent minute oscillations. The relatively large number of modes that may exist in gi- ant stars means that these objects may be amenable to asteroseismic tech- niques. Asteroseismology is one of the next milestones in astrophysics, and presently there are relatively few class- es of stars on which these techniques can be applied, so it is important when more such objects are discovered. Asteroseismology can be used to de- rive such fundamental stellar parame- ters as mass and radius. This is partic- ularly useful for giant stars as these oc- cupy a region of the H–R diagram where it is difficult to obtain accurate stellar parameters. Furthermore, the evolutionary tracks of main-sequence stars in the spectral range A-G, all con- verge on the giant branch, so it is im- possible to establish the nature of the progenitor star only from these theoret- ical tracks. Asteroseismology may play Figure 1: Ca II K line observations of one of the target stars. Observations taken in different a key role in understanding the stellar nights are overlapped. In case of rotational modulation induced by surface inhomogeneities, properties, structure, and evolution of the chromospheric core of this line will show detectable variations. 13 (2) its high effi- proaching that of other, state-of-art ciency permitted techniques. We will outline our method- the acquisition of ology in the data reduction and provide data on a large some tips for the potential users. sample of stars in one night, and fi- 3. Pushing the FEROS nally, Capabilities (3) the radial velocity accuracy Although not conceived explicitly for of 23 m/s, which very accurate radial-velocity measure- was shown during ments (original requirements were set the commission- to an accuracy of 50 m/sec), FEROS ing period (Kaufer has been equipped with a double-fibre et al. 1999) was at system, where the second fibre can be a level adequate used either for recording the sky or for for the study of gi- obtaining simultaneous calibration ant variability. We spectra to the science exposure (see also were confi- Fig. 3, which shows a part of a frame dent that the containing the stellar and simultaneous FEROS perform- calibration spectra), following the tech- ances could be nique pioneered by the Geneva group improved with a with ELODIE and CORALIE (Baranne targeted strategy et al. 1996). Figure 2: H-R diagram for the 63 stars observed so far for our pre - and by upgrading By using a simple cross-correlation cise radial velocity survey with FEROS. The sample well covers the the software and (Kaufer et al., 1999, see also FEROS Red Giant Branch and the “clump” region. the data analysis. user manual) in the commissioning As part of the time, it was shown that FEROS could targets for VLTI observations (von der ESO time on FEROS we obtained in obtain a radial-velocity accuracy of 23 Lühe et al. 1996). Periods 64 and 65 a total of 5 full and 6 m/sec by observing every night the G The non-radial g-mode oscillations half nights. An additional 12 half nights star HD10700 (Tau Cet), an object seem unlikely, since these are not ex- were allocated as part of the Brazilian which has been demonstrated to have pected to propagate through the deep time. Early in our programme, after sur- a radial velocity constant to better than outer convection zone in these stars, veying only 27 stars, we had indications 5 m/s (Butler et al. 1996). but nature is always full of surprises. that 80% of our target objects showed A “constant’’ star is extremely useful Alternatively, these long-period varia- variations on the time-scales of a few to to estimate the long-term accuracy of tions may represent more exotic pulsa- hundreds of days. This is consistent FEROS and to provide a standard for tions such as toroidal modes. The plan- with the results of earlier, more limited optimising the radial velocity analysis. et hypothesis is supported by these pe- surveys. Variability in G and K giants Demonstrating a lack of RV variability riods being long lived (for more than 12 may indeed be ubiquitous. In Period 65 in a standard star would make us more years) and coherent. In the case of the we could enlarge the sample which confident of our results on variable star Aldebaran, the long-period RV vari- now consists of 63 stars covering a stars in the programme. For this pur- ations were not accompanied by line- large fraction of the upper HR-diagram. profile variations (Hatzes & Cochran The H-R diagram of the observed stars 1998). Although these seem to exclude is shown in Figure 2. From this figure it rotations and pulsations, conclusive ev- is clear that the sample spans the idence in support of the planetary hy- whole Red Giant Branch as well as the pothesis has proved elusive. region of the “clump”. The targets were selected on the basis of accurate HIP- 2. Observations PARCOS parallaxes in order to ensure a reliable determination of the basic K giant RV variability is still a largely stellar parameters. The high resolution unexplored area. Not only is the nature and high S/N ratio of the FEROS spec- of the long-period variations unknown, tra will also allow the spectroscopic de- but a knowledge of the characteristics termination of effective temperatures, of the short-period (p-mode) oscilla- gravities and metallicities. With such an tions as a function of a giant’s position extensive data base it will be possible in the H–R diagram is also lacking. to investigate the dependence of the ra- For these reasons, in ESO Period 64 dial velocity variability on a wide variety (October 1999 – April 2000), we started of stellar parameters, including the es- an unprecedented survey of precise ra- timated stellar mass and evolutionary dial-velocity measurements as a Euro- status. This is important for calibrating pean-Brazilian collaboration aimed at theoretical evolutionary tracks.
Load more

Recommended publications
  • The Search for Extrasolar Planets
    zucker 16-12-2005 11:22 Pagina 229 229 The Search for Extrasolar Planets S. Zucker and M. Mayor Observatoire de Genève, Sauverny, Switzerland During the recent decade, the question of the existence of planets orbiting stars other than our Sun has been answered unequivocally. About 150 extrasolar plan- ets have been detected since 1995, and their properties are the subject of wide interest in the research community. Planet formation and evolution theories are adjusting to the constantly emerging data, and astronomers are seeking new ways to widen the sample and enrich the data about the known planets. In September 2002, ISSI organized a workshop focusing on the physics of “Planetary Systems and Planets in Systems”1. The present contribution is an attempt to give a broader overview of the researches in the field of exoplanets and results obtained in the decade after the discovery of the planet 51 Peg b. The existence of planets orbiting other stars was speculated upon even in the 4th century BC, when Epicurus and Aristotle debated it using their early notions about our world. Epicurus claimed that the infinity of the Universe compelled the existence of other worlds. After the Copernican Revolution, Giordano Bruno wrote: “Innumerable suns exist; innumerable earths revolve around these suns in a manner similar to the way the seven planets revolve around our Sun”. Aitken2 examined the observational problem of detecting extrasolar planets. He showed that their detection, either directly or indirectly, lay beyond the techni- cal horizon of his era. The basic difficulty in directly detecting planets lies in the brightness ratio between a typical planet and its host star, a ratio that can be as low as 10-8.
    [Show full text]
  • The Astronomy Department of the University of Geneva (UNIGE) and Its Exoplanet Team
    Département D'Astronomie Chemin des Mailletess 5 Université De Genève CH-5290 Versoix Sauverny Switzerland +45 22 379 22 00 [email protected] www.unige.ch/sciences/astro/en/ The Astronomy Department of the University of Geneva (UNIGE) and its Exoplanet Team About the Astronomy Department The Department of Astronomy of the University of Geneva (UNIGE) is located on the commune of Versoixs 5 km from the Geneva city center. The main buidings (l’Observatoire) are in the forest on the site of Sauvernys km from the town of Versoix. Another sites Ecogias closer to town hosts most of our space developments. Grounded in 5772 as the Geneva Observatory the insttute became the Department of Astronomy of UNIGE in 5973. Todays a group of approximately 5 0 people are employeds including scientstss PhD candidatess studentss technical staf (computer and electronics specialistss mechanics)s as well as administratve staf. The Astronomy Department manages a permanent astronomical observaton statonn a 5s2 m telescope on the site of La Silla (ESOs Chile). Observatons are also regularly obtained with the other ESO facilitess from the 5.93m telescope on the site of St-Michel (Observatory of Haute Provences OHPs France)s and from La Palma (Canary Islandss Spain). Astronomy Department Research Overview Research in the Department of Astronomy is described according to the Roadmap for Astronomy in Switzerland 2007-2056 four main themesn Exoplanetary systems Stars formaton evoluton Galaxies Universe Extreme Universe Main Building of the Astronomy Department in Versoix/Geneva 5 Département D'Astronomie Chemin des Mailletess 5 Université De Genève CH-5290 Versoix Sauverny Switzerland +45 22 379 22 00 [email protected] www.unige.ch/sciences/astro/en/ Research at the Exoplanetary Group The discovery of planets orbitng other stars (exoplanets) has been one of the major breakthroughs in astronomy of the past decades.
    [Show full text]
  • CV En Didier Queloz.Pdf
    1 CURRICULUM VITAE Didier Queloz July 2012 Date of birth 23 February 1966 Nationality Swiss Current Position Professor, Geneva University, Geneva Observatory 51ch des Maillettes, CH-1290 Sauverny Switzerland Academic degrees 1990 Master in physics, Geneva University 1992 Astronomy and Astrophysics Certificate (DEA) 1995 PhD with Prof M. Mayor “Research by cross-correlation techniques”, Geneva University Awards § Science quotation (1995) for Discovery of the first extra-solar planet as on of the 10 most important discovery of the year § “Vacheron Constantin” prize (1996) for best phD of the Geneva science faculty § “Balzers” prize from the Swiss Physical Society (1996) for the discovery of the planet orbiting the star 51Peg § IAU Medal of honor (1996) commission 51 Bioastronomy § “Prix de la ville de Genève” 2011, Science category § BBVA Foundation Frontiers of Knowledge Awards 2011 § Honorary degrees from Employments 1996-1997 Post-doc, Geneva University 1997-1999 Distinguished visiting scientist, Jet Propulsion Lab, CA, USA 2000-2002 Research associate (“maitre assistant”), Geneva University 2003-2007 Faculty (“MER”), Geneva University 2008 Professor (PAD), Geneva University Professional service and committees • ESA Scientific Advisory group for IRSI-DARWIN (1997-2001) • IAU “radial velocity commission” (1997-2006) 2 • Board of the science advisory councilors of the OHP (1997-2000) • Study science team for PRIMA (ESO) (1998-2000) • ESO Observation Program Committee (OPC) (ESO telescope allocation) (2000-2001) • ESA Astronomical Working
    [Show full text]
  • Abstracts of Extreme Solar Systems 4 (Reykjavik, Iceland)
    Abstracts of Extreme Solar Systems 4 (Reykjavik, Iceland) American Astronomical Society August, 2019 100 — New Discoveries scope (JWST), as well as other large ground-based and space-based telescopes coming online in the next 100.01 — Review of TESS’s First Year Survey and two decades. Future Plans The status of the TESS mission as it completes its first year of survey operations in July 2019 will bere- George Ricker1 viewed. The opportunities enabled by TESS’s unique 1 Kavli Institute, MIT (Cambridge, Massachusetts, United States) lunar-resonant orbit for an extended mission lasting more than a decade will also be presented. Successfully launched in April 2018, NASA’s Tran- siting Exoplanet Survey Satellite (TESS) is well on its way to discovering thousands of exoplanets in orbit 100.02 — The Gemini Planet Imager Exoplanet Sur- around the brightest stars in the sky. During its ini- vey: Giant Planet and Brown Dwarf Demographics tial two-year survey mission, TESS will monitor more from 10-100 AU than 200,000 bright stars in the solar neighborhood at Eric Nielsen1; Robert De Rosa1; Bruce Macintosh1; a two minute cadence for drops in brightness caused Jason Wang2; Jean-Baptiste Ruffio1; Eugene Chiang3; by planetary transits. This first-ever spaceborne all- Mark Marley4; Didier Saumon5; Dmitry Savransky6; sky transit survey is identifying planets ranging in Daniel Fabrycky7; Quinn Konopacky8; Jennifer size from Earth-sized to gas giants, orbiting a wide Patience9; Vanessa Bailey10 variety of host stars, from cool M dwarfs to hot O/B 1 KIPAC, Stanford University (Stanford, California, United States) giants. 2 Jet Propulsion Laboratory, California Institute of Technology TESS stars are typically 30–100 times brighter than (Pasadena, California, United States) those surveyed by the Kepler satellite; thus, TESS 3 Astronomy, California Institute of Technology (Pasadena, Califor- planets are proving far easier to characterize with nia, United States) follow-up observations than those from prior mis- 4 Astronomy, U.C.
    [Show full text]
  • A Three-Planet Extrasolar System
    quires that common properties in all the Acknowledgements Koch A. et al. 2006a, The Messenger 123, 38 dSphs be identified – we must therefore Koch A. et al. 2006b, AJ 131, 895 Mark I. Wilkinson acknowledges the Particle Physics Majewski S. R. et al. 2005, AJ 130, 2677 carry out similar studies of all dSphs. and Astronomy Research Council of the United Martin N. et al. 2006, MNRAS 367, L69 Kingdom for financial support. Andreas Koch and Mateo M. et al. 1993, AJ 105, 510 Finally, in the area of dynamical model- Eva K. Grebel thank the Swiss National Science Mateo M. 1997, ASP Conf. Ser. 116, 259 ling, identifying correlations between the Foundation for financial support. Mateo M. et al. 1998, AJ 116, 2315 Monelli M. et al. 2003, AJ 126, 218 kinematics and abundances of the stel- Munoz R. R. et al. 2005, ApJ 631, L137 lar populations in dSphs (e.g. Tolstoy et References Shetrone M. D. et al. 2001, ApJ 548, 592 al. 2006) is likely to provide important Tolstoy E. et al. 2006, The Messenger 123, 33 new information about the formation and Aaronson M. 1983, ApJ 266, L11 Wilkinson M. I. et al. 2002, MNRAS 330, 778 Belokurov V. et al. 2006, ApJL, submitted, Wilkinson M. I. et al. 2004, MNRAS 611, L21 evolution of these objects, which in turn astro-ph/0604355 Wilkinson M. I. et al. 2006, in proceedings of XXIst will further constrain models of any astro- Goerdt T. et al. 2006, MNNRAS 368, 1073 IAP meeting, EDP sciences, astro-ph/0602186 physical feedback on their dark matter.
    [Show full text]
  • Who Really Discovered the First Exoplanet?
    Who Really Discovered the First Exoplanet? Two Swiss astronomers got a well-deserved Nobel for finding an exoplanet, but there’s an intriguing backstory By Josh Winn The year 1995, like 1492, was the dawn of an age of discovery. The new explorers, instead of using seagoing vessels to discover continents, use telescopes to discover planets revolving around distant stars. Thousands of these extrasolar planets, a term usually shortened to “exoplanets,” have been found, including a few potentially Earth- like worlds, along with bizarre objects that bear no resemblance to any of the planets in our solar system. Two of these exoplanet explorers, Michel Mayor and Didier Queloz, were recently awarded half of the Nobel Prize in Physics for the discovery they made in 1995. My colleagues and I are united in our admiration for their pioneering work, and in our pride to be continuing what they began. But there is something peculiar about the Nobel Prize citation. It says: “for the discovery of an exoplanet orbiting a solar-type star.” Shouldn’t it say the first exoplanet? After all, hundreds of astronomers have discovered an exoplanet. I’ve helped find a few. Even high school students and amateur astronomers have discovered them. Did the Nobel Committee make a typographical error? No, they did not, and thereby hangs a tale. Just as it is problematic to decide who discovered America (Christopher Columbus? John Cabot? Leif Erikson? Amerigo Vespucci, whose name is the one that stuck? Those who came on foot from Siberia tens of thousands of years ago?) it is difficult to say who discovered the first exoplanet.
    [Show full text]
  • A Catalog of Rotational and Radial Velocities for Evolved Stars V
    A&A 561, A126 (2014) Astronomy DOI: 10.1051/0004-6361/201220762 & c ESO 2014 Astrophysics A catalog of rotational and radial velocities for evolved stars V. Southern stars, J. R. De Medeiros1,S.Alves1,S.Udry2, J. Andersen3,4,B.Nordström3, and M. Mayor2 1 Departamento de Física, Universidade Federal do Rio Grande do Norte, Campus Universitário, 59072-970 Natal, RN, Brasil e-mail: [email protected] 2 Observatoire de Genève, Université de Genève, Chemin des Maillettes 51, 1290 Sauverny, Switzerland 3 The Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen, Denmark 4 Nordic Optical Telescope, Apartado 474, 38700 Santa Cruz de La Palma, Spain Received 19 November 2012 / Accepted 10 December 2013 ABSTRACT Rotational and radial velocities have been measured for 1589 evolved stars of spectral types F, G, and K and luminosity classes IV, III, II, and Ib, based on observations carried out with the CORAVEL spectrometers. The precision in radial velocity is better than 0.30 km s−1 per observation, whereas rotational velocity uncertainties are typically 1.0 km s−1 for subgiants and giants and 2.0 km s−1 for class II giants and Ib supergiants. Key words. stars: late-type – stars: fundamental parameters – binaries: spectroscopic – techniques: radial velocities – catalogs – stars: evolution 1. Introduction enabling reliable investigations of stellar rotational character- istics in different regions of the H−Rdiagram(Carlberg et al. Over the past two decades, observations have been carried out at 2011; Cortés et al. 2009; Melo et al. 2001), the relation- the Geneva Observatory, Switzerland, and the Federal University ship between rotation and different stellar properties (Monaco of Rio Grande do Norte, Brazil, to accurately measure projected v et al.
    [Show full text]
  • Dr. Avi Mandell (NASA) “Somewhere, Something Incredible Is Waiting to Be Known.” - Carl Sagan
    The Age of Exoplanets: From First Discoveries to the Search for Living Worlds Dr. Avi Mandell (NASA) “Somewhere, something incredible is waiting to be known.” - Carl Sagan How will the discovery of a distant planet teeming with life change our perspective on our own planet – and on ourselves? Planets 101: Our Solar SysteM Planets 101: Our Solar SysteM First Planet Around a Sun-Like Star Discovered in 1995 Notable Facts About 1995: • Bill Clinton is in his 3rd year of the Presidency • Ebay opens for business •DVDs are first introduced •Big event for the coffee-drinking world… Invention of the Frappucino! The First Planets were Discovered by Measuring The Motions of Stars 51 Peg b • Uses the change in star’s light due to the Doppler effect Mayor & Queloz, Movie: eso1035g.mov November 1995 Dr. Michel Mayor & Dr. Didier Queloz Geneva Observatory Spectrum of Starlight from Dr. Geoff Marcy & Parent Star Dr. R. Paul Butler San Francisco State Univ. Timeline of Exoplanet Discoveries Known Exoplanets, 1995: 0 Planet Mass Jup. Neptune Earth Mercury Earth Jupiter Distance to the Star Timeline of Exoplanet Discoveries Known Exoplanets, 1996: 6 Planet Mass Jup. First Confirmed RV Planet: 51 Peg b Neptune Earth Mercury Earth Jupiter Distance to the Star Timeline of Exoplanet Discoveries Known Exoplanets, 1996: 6 2000: 38 Planet Mass First Transiting Planet: Jup. HD 209458 b First Confirmed RV Planet: 51 Peg b Neptune Earth Mercury Earth Jupiter Distance to the Star The Most Planets have been Discovered by Measuring The Shadows on Stars Movie: OccultationGraphH264FullSize.mov Timeline of Exoplanet Discoveries Known Exoplanets, 2000: 38 2005: 155 2008: 260 2012: 579 Planet Mass Jup.
    [Show full text]
  • THE STELLAR VARIABILITY from HIPPARCOS PHOTOMETRY M. GRENON Geneva Observatory 1290 Sauverny, Switzerland 1. Introduction During
    THE STELLAR VARIABILITY FROM HIPPARCOS PHOTOMETRY M. GRENON Geneva Observatory 1290 Sauverny, Switzerland 1. Introduction During the development of the Hipparcos satellite, the opportunity to use the star mapper to perform a whole sky two colour intermediate accuracy photometric survey, and the main-mission detector for high accuracy photometry of target stars was identified. The instrument was optimised and the pre-launch calibrations performed to pre-determine the pass-bands with an accuracy suf­ ficient to cope, in-orbit, with the foreseen aging of the detection chains. Photometry became an important by-product of the mission, very complementary to the astrometric results. It was the first opportunity to monitor the sky during 3-4 years without selection biases and with a precision similar to that achieved from the ground with the best classical techniques. A systematic detection of small amplitude variables was the expected return. 2. The correction of the aging effect The radiation by cosmic and solar particles induced transmission losses mainly in the green to violet part of the spectrum. Since the Hp band is broad, AA 380-900 nm, the effect was a chromatic change of the band, and hence of the Hp magnitude as large as 0.6 and 0.2 mag over the mission for V-I = 0 and 7 mag respectively. Photometric reductions were performed twice a day using a subset of the 29000 standard stars. Zero-point errors on the magnitude scale were then less than 0.001 mag for each data set. Correction of chromatic drifts requires the knowledge of the star colour; consequently error on it induces a linear trend in the Hp time series.
    [Show full text]
  • List of Participants
    LIST OF PARTICIPANTS H. ABLES, US Naval Observatory, Flagstaff, USA M. ANDRACACOU, Dept. of Astronomy, University of Athens, Greece E. ANTONOPOULOU, Dept. of Astronomy, University of Athens, Greece I. APPENZELLER, Landessternwarte Konigstuhl, Heidelberg, Germany T. ARMANDROFF, Yale University Observatory, New Haven, CT, USA M. AZZOPARDI, European Southern Observatory, München, Germany G. BERTELLI, Istituto di Astronomia, Padova, Italy G. BODIFEE, Astrofysisch Instituut, University of Brussels, Belgium. Β. BOHANNAN, university of Colorado, Boulder, USA J. BREYSACHER, European Southern Observatory, München, Germany A. CAMPBELL, Institute of Astronomy, Cambridge, England C. CHIOSI, Istituto di Astronomia, Padova, Italy M. CHRYSSOVERGIS, University of Athens, Greece Y. CHU, Astronomy Dept., University of Illinois, Urbana, USA P. CONTI, University of Colorado, Boulder, USA A. DAPERGOLAS, National Observatory Athens, Greece J.P. DE GREVE, Astrofysisch Instituut, University of Brussels, Belgium. M. DE GROOT, Armagh Observatory, Northern Ireland C. DE JAGER, Space Research Laboratory, Utrecht, the Netherlands C. DE LOORE, Astrofysisch Instituut, University of Brussels, Belgium. P. DUBOIS, Observatoire de Strasbourg, France M. FEAST, South African Astronomical Observatory, South Africa W. FREEDMAN, Mount Wilson and Los Campanos Observatory, Pasadena, California, USA E. GAVRYUSEVA, Inst, for Nuclear Research, Acad, of Sciences, Moscow, U.S.S.R. J. GRAHAM, Joint Institute for Laboratory Astrophysics University of Colorado and National Bureau of Standards, USA. L. GREGG10, Istituto di Astronomia, Padova, Italy. D. HATZIDIMITRIOÜ, National Observatory Athens, Greece P. HELLINGS, Astrofysisch Instituut, University of Brussels, Belgium. D. HILLIER, Mt. Stromlo Observatory, Woden P.O., Australia P. HODGE, Astronomy Dept. University of Washington, Seattle USA J. HOESSEL, Space Telescope Science Institute, Baltimore, USA I. HOWARTH, Dept.
    [Show full text]
  • The Physical Tourist Geneva: from the Science of the Enlightenment to CERN*
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by RERO DOC Digital Library Phys. perspect. 9 (2007) 231–252 1422-6944/07/020231–22 DOI 10.1007/s00016-007-0327-5 The Physical Tourist Geneva: From the Science of the Enlightenment to CERN* Jan Lacki** John Calvin (1509–1564) founded a College and Academy in Geneva in 1559, the latter of which, through the efforts of many of its scholars, was finally declared to be a genuine university,the Uni- versity of Geneva, in 1872. Meanwhile, thanks to the outstanding achievements of the rich, patri- cian Genevan scientists, in particular during the 18th century, Geneva secured a prominent place in European learned society. With the appointment of Charles-Eugène Guye (1866–1942) to the University of Geneva in 1900, Genevan research entered resolutely into 20th-century physics, par- ticularly relativity,and continued to gain momentum before and after the Second World War when, in 1953, Geneva was chosen as the site of one of the most prestigious scientific laboratories in the world,CERN.I sketch these developments,pointing out many of the locations where they occurred in Geneva. Key words: Geneva College and Academy; Geneva Observatory; University of Gene- va; Institute of Physics; Museum of History of Science; CERN; John Calvin; Carl Vogt; Jean-Robert Chouet; Jacques-André Mallet; Emile Gautier; Horace-Bénédict de Saussure; Pierre Prévost; Gaspard de la Rive; Auguste de la Rive; Charles-Eugène Guye; Albert Einstein; Ernest C.G. Stueckelberg; physics; astronomy; history of physics; scientific instruments; theory of relativity; quantum theory.
    [Show full text]
  • The Catalogue of Radial Velocity Standard Stars for Gaia I. Pre-Launch
    Astronomy & Astrophysics manuscript no. RV˙final c ESO 2018 March 19, 2018 The catalogue of radial velocity standard stars for Gaia ⋆ ⋆⋆ I. Pre-launch release C. Soubiran1, G. Jasniewicz2, L. Chemin1, F. Crifo3, S. Udry4, D. Hestroffer5, and D. Katz3 1 LAB UMR 5804, Univ. Bordeaux - CNRS, F-33270, Floirac, France e-mail: [email protected] 2 LUPM UMR 5299 CNRS/UM2, Universit´eMontpellier II, CC 72, 34095 Montpellier Cedex 05, France 3 GEPI, Observatoire de Paris, CNRS, Universit´eParis Diderot, 5 place Jules Janssen, 92190 Meudon, France 4 Observatoire de Gen`eve, Universit´ede Gen`eve, 51 Ch. des Maillettes, 1290 Sauverny, Switzerland 5 IMCCE, Observatoire de Paris, UPMC, CNRS UMR8028, 77 Av. Denfert-Rochereau, 75014 Paris, France Received March 19, 2018; accepted XX ABSTRACT The Radial Velocity Spectrograph (RVS) on board of Gaia needs to be calibrated using stable reference stars known in advance. The catalogue presented here was built for that purpose. It includes 1420 radial velocity standard star candidates selected on strict criteria to fulfil the Gaia-RVS requirements. A large programme of ground-based observations has been underway since 2006 to monitor these 1 stars and verify their stability, which has to be better than 300 m s− over several years. The observations were done on the echelle spectrographs ELODIE and SOPHIE on the 1.93-m telescope at Observatoire de Haute-Provence (OHP), NARVAL on the T´elescope Bernard Lyot at Observatoire du Pic du Midi and CORALIE on the Euler-Swiss Telescope at La Silla. Data from the OHP and Geneva Observatory archives have also been retrieved as have HARPS spectra from the ESO archive.
    [Show full text]