Stockholm Observatory Annual Report 2007

STOCKHOLM OBSERVATORY

ANNUAL REPORT 2007

Stockholm Observatory, AlbaNova University Center, SE-106 91 Stockholm, Sweden

www.astro.su.se Editor: Soﬁa Ramstedt Front page image: A composite of pictures taken during the mounting of the new 1 m telescope in the dome at AlbaNova. Credit: Michael Blomqvist, Robert Cumming, and Teresa Riehm.

Stockholm Observatory, AlbaNova University Center, SE-106 91 Stockholm, Sweden

www.astro.su.se 3

PREFACE

The year 2007 marked the official start for the new structure of undergraduate education at Swedish universities, usually referred to as the Bologna process. The transition from basically four year programmes to a system with two exams after three and two years respectively, is a major one and it will probably take a few years before the new scheme works smoothly. Another focal point of the year was the working environment. This was the main theme during our yearly one-day departmental meeting. A number of issues were brought up and discussed. Partly as a follow-up to this, an afternoon was later spent analysing and discussing the results from a questionnaire with a similar aim. This provided a range of measures that need to be taken and suggestions on how they should be implemented. It will be one of the main tasks for the coming years to ensure that the good intentions shown during these meetings are transformed into fruitful changes in the way we work together for the betterment of the Observatory. During the year Tanja Nymark, Luis Borgonovo, and Matthew Hayes presented and successfully defended their PhD-theses. At the same time, Martina Friedrich, Javier Blasco Herrera, Vasco Henriques, and Andrej Kuutmann joined our graduate programme. Magnus Näslund started a permanent position as “universitetsadjunkt” and Kambiz Fathi accepted a four year position as research associate financed by the Swedish Research Council. RenéLiseau and Kay Justtanont left the Observatory to take upp positions at the Onsala Space Observatory, while Edvard Mörtsell was offered a permanent position as associate professor at the Physics department here at AlbaNova. After almost six years, the Observatory is again an observatory in the true sense of the word. The arrival of the 1-m telescope arose much joy and was duly celebrated. It is going to be shared with the environmental group in the Physics department at KTH and, hence, is a good example of the interdisciplinary projects made possible by the establishment of AlbaNova.

April 2008 Claes-Ingvar Bj¨ornsson, Director (2002-2007) 4

1. INTRODUCTION

The Department of Astronomy at Stockholm University (Stockholm Observatory) has responsibilities in teaching, research and public outreach. The department hosts The Institute for Solar Physics of the Royal Swedish Academy of Sciences [Kungliga Vetenskapsakademiens institut för solfysik]. About 60 people were actively engaged at the department during 2007, including close to 30 graduate students. The fields of research include the interstellar medium and star formation, young stars and planetary systems, solar physics, evolved stars and planetary nebulae, supernovae, galactic structure and dynamics, observational cosmology, and high energy astrophysics. Besides, instruments were developed in the Observatory workshop. Stockholm Observatory made use of many instruments at the European South- ern Observatory (ESO), including the Very Large Telescope (VLT). The Swedish Solar Telescope (SST) operated by the Institute for Solar Physics, and the Nordic Optical Telescope (NOT) are both extensively used by researchers at Stockholm Observatory and are located on La Palma, Canary Islands. Other ground-based instruments were also used, like the 20 m antenna at the Onsala Space Observatory (OSO), the Atacama Pathfinder Experiment (APEX) located on Llano Chajnantor, Chile, the James Clerk Maxwell Telescope (JCMT) on Mauna Kea, Hawaii, and the IRAM 30 m telescope on Pico Veleta, Spain. Various research programs at the Observatory make use of space-based observatories including the swedish space-born radio telescope Odin, the Hubble Space Telescope (HST), the International Gamma-Ray Astrophysics Laboratory (INTE- GRAL), the Compton Gamma-Ray Observatory (CGRO), the Rossi X-ray Timing Explorer (RXTE), the X-ray Multimirror Mission (XMM), and the X-ray Observa- tory (CHANDRA). Observatory members are also actively involved in the development of, and program planning for, new space missions such as the far infra-red space telescope Herschel, the infrared space interferometer Darwin, the Gamma-ray Large Area Space Telescope (GLAST), the Polarized Gamma-ray Observer (Light weight version) (PoGOLite), and the James Webb Space Telescope (JWST). 5

2. UNIVERSITY COURSES

Stockholm Observatory is the Department of Astronomy at Stockholm University. As such, it offers a number of undergraduate and graduate courses in astronomy and has programs leading to the bachelor, master, licentiate and PhD degrees. In 2007, the director for undergraduate studies [studierektor för grundutbildningen] was Peter Lundqvist and the student counselor [studievägledare] was Magnus Axelsson. The director for the Graduate School [studierektor för forskarutbildningen] was Hans Olofsson. Ulla af Petersens (formerly Engberg) was in charge of the student office. During 2007 a new structure of the undergraduate education (’the Bologna process’) was introduced at the Department of Astronomy. The undergraduate education is now more formally divided into two parts; the first three years leading to a bachelor degree with the possibility to continue the studies for an additional two years leading to a master degree. During a transitional period, courses within the old four-year program (’magister’) are taught simultaneously as the new master courses. In addition, general admission courses are taught (in swedish only) as usuall. The courses taught in 2007 are listed below.

2.1. Undergraduate Courses

General Admission Courses [Orienteringskurser]

Spring semester Oversiktskurs¨ i astronomi Astronomiska världsbildens utveckling Om planeter och liv i universum Summer semester Oversiktskurs¨ i astronomi Människan i rymden Autumn semester Astronomi kontra astrologi ur ett vetenskapligt perspektiv Solen och andra stjärnor Modern astronomi

Basic Level Courses [Kurser p˚agrundniv˚a]

Spring semester Galaxies and cosmology [Galaxer och kosmologi] 6

Advanced Level Courses [Kurser p˚aavancerad niv˚a]

Spring semester Observational techniques in astronomy I [Astronomisk observationsteknik I] Observational techniques in astronomy II [Astronomisk observationsteknik II] Astrophysical spectra [Astrofysikaliska spektra] Stellar structure and evolution [Stj¨arnornas struktur och utveckling] Autumn semester Astrophysical gas dynamics [Astrofysikalisk gasdynamik] Radiation processes in astrophysics [Astrofysikaliska str˚alningsprocesser] Galaxies [Galaxer] Interstellar medium [Interstell¨ara mediets fysik] Cosmology [Kosmologi]

2.2. Graduate Courses The course work part within the graduate studies programme corresponds to 90 hp (1.5 hp corresponds to one week of full-time studies). The graduate studies programme in astronomy has three tracks to choose from: astrobiology, astronomy, and high-energy astrophysics and cosmology. All three are divided into one part of 52.5 hp common to all student within that track, and an individual part of 37.5 hp. Some courses are taught in collaboration with or by the Physics Department of Stockholm University. Some courses may be self-study courses. During 2007, the following courses were taught:

Spring semester Late stages of stellar evolution [Stj¨arnornas sena utveckling] Molecules in space and planetary atmospheres 7

3. THESES DEFENDED IN 2007

PhD

Kramer Nymark T., March 2007, X-ray emission from supernova shock waves, supervisor: C. Fransson

Borgonovo L., May 2007, Spectral and Temporal Studies of Gamma-Ray Bursts, supervisors: R. Svensson & C-I. Bj¨ornsson

Hayes M., September 2007, Lyman-alpha imaging of starburst galaxies in the local universe and beyond, supervisor: G. Ostlin¨

Master theses

Martinsson T., January 2007, Monsters or lens lice? An investigation of unusually bright Lyman Break Galaxies, supervisor: G. Ostlin¨

Bast J., February 2007, SiS line emission as a probe of chemistry and grain formation in circumstellar envelopes of AGB stars, supervisor: F. L. Sch¨oier

Kuutmann A., October 2007, Photo-evaporation of Globulettes, supervisor: G. Mellema 8

4. RESEARCH

4.1. Star Formation Regions, Young Stars and Astrobiology (Z. Banhidi, A. Brandeker, H.-G. Flor´en, G. Gahm, M. G˚alfalk, K. Justtanont, A. Kuutmann, B. Larsson, R. Liseau, G. Mellema, R. Nilsson, G. Olofsson, S. Olofsson, Aa. Sandqvist) The research at the Stockholm Observatory in the ﬁeld of star formation is oriented along four major lines:

(i) The study of the interstellar medium, in particular the chemistry, physics and evolution of molecular clouds, star forming clouds, and the molecular emission and polarization from circumstellar environments. (ii) The study of ensembles of very young stellar objects, aiming to determine empirically the mass spectrum of stars at their birth. The functional form of this spectrum appears universal, i.e., it is the same in our Galaxy and in external galaxies. Our primary objective is to understand to what degree the memory of the initial cloud condition is frozen in this spectrum. (iii) The study of the dynamics of forming stars, especially during the earliest, protostellar phases. The physics of the mass building infall and the coexisting mass outﬂows are not well understood. These processes are of major interest since they determine the ﬁnal stellar mass and the formation of planets. (iv) The study of young stars of low and intermediate mass, and the evolution of accretion disks.

Figure 1. Young stars with dusty disks in the Orion nebula observed using NOT. To the left a disk is seen in reﬂected light from the bright stars in the surroundings, and to the right the disk is seen absorbing the background light.

A number of projects are based on observations collected at diﬀerent telescopes such as the Infrared Space Observatory (ISO), HST, XMM, CHANDRA, ODIN, APEX, NOT, ESO (VLT), and group members were involved in the preparations for HERSCHEL, JWST and DARWIN. Various theoretical studies are made for interpreting the observations. For instance, state of the art multi-dimensional hy- drodynamic simulations are also used for the interstellar medium studies. 9

4.2. Astrophysics of Planetary Systems (P. Thebault, G. Mellema, A. Brandeker, A. Grigorieva, A. Peplinski, M. de Val Borro, R. Nilsson, A. Kuutmann) The group’s focus is on theoretical investigation of the origins of planetary systems around stars. The three main areas of study are as follows: (i) Primordial solar nebulae with embedded protoplanets. Nearly 300 exoplanets (planets around stars other than the sun) have been discovered to date. Most of them have masses and orbital parameters surpris- ingly dissimilar to our own system. Theoretical understanding of these char- acteristics requires a thorough knowledge of how the protoplanets growing in accretion disks interact with them. Our group studies these interactions both analytically and using sophisticated multidimensional hydrodynamical simulations (for movies see http://www.astro.su.se/∼pawel/planets/movies.html). (ii) Circumstellar dust discs. Planet formation takes place in a protoplanetary nebulae rich in gas. Once most of the planet formation process is over, most of the gas disapears and what is left is a ”debris” disc, made from solid bodies not used in building planets. When observing these discs what we see are only very small particles (<1 millimetre), but it is very likely that these small grains are steadily produced from collisions amongst much larger and undetectable objects. Our group is involved in both observational characterizations of these systems and in theoretical models of the physical processes at play. We have developed models to study the global collisional and dynamical evolution of circumstellar discs, but also the chemical characterization of the observed dust grains. (see for example http://www.astro.su.se/news/20070621en.html or http://www.obspm.fr/actual/nouvelle/sep06/avalanche.en.shtml)

Figure 2. Synthetic images of a typical extended debris disk at diﬀerent wavelengths.

(iii) Planetesimal accretion in binary system. Most stars are members of binary or multiple systems, making the study of planets in such systems a very relevant issue. This issue has been made all the more timely by the discovery of more than 40 extrasolar planets in multiple systems. We have developed numerical models to study how one crucial stage of the planet formation scenario, the mutual accretion of kilometre–sized plan- etesimals, is aﬀected by the presence of a companion star. Our main result is that, for binaries of separation < 40AU, the coupled eﬀect of the secondary’s gravity and gaseous friction always strongly perturbs and sometimes even stops the planetesimal growth process. 10

4.3. AGB stars and post-AGB objects (K. Justtanont, M. Maercker, H. Olofsson, S. Ramstedt, F. Schöier) The research at the Stockholm Observatory in this area centers on the properties of stellar mass loss on the AGB (Asymptotic Giant Branch), and the subsequent evolution of these objects beyond the AGB. Extensive multi-transition, single-dish CO line surveys, as well as surveys in other molecular line emissions, of large samples of M-type stars and carbon stars form the observational basis of our work. However, it is also necessary to use a multi-wavelength (radio to UV) and a multi-method (radio interferometers to space-borne telescopes) approach. The different methods of exploration are complementary and disclose different regions at different spatial resolution and reflect different chemical properties of the envelopes. We have in particular used ISO observations and Odin to put constraints on the conditions in the inner parts of the circumstellar envelopes (CSEs), radio interferometry observations to obtain information on intermediate regions, and imaging in scattered stellar light to supplement the radio observations of the coldest outer regions. Detailed radiative transfer models, combined with a physical/chemical model of the CSE, are used to derive quantitative results from molecular line and dust continuum data, such as reliable mass loss rates, molecular abundances, and isotope ratios.

Figure 3. The detached shell around the carbon star DR Ser. The light is scattered by dust in the shell. The image was taken with the PolCor instrument on the NOT in Spring 2007. 11

4.4. Supernovae (C.-I. Björnsson, C. Fransson, P. Gröningsson, A. Jerkstrand, C. Kozma, P. Lundqvist, S. Mattila, J. Melinder, E. Mörtsell, T. Nymark, J. Sollerman, A. Tziamtzis) The supernova group at Stockholm observatory works with both observations and modeling. On the observational side, much of the effort has been put into optical observations with the VLT telescopes, but also space based observations with HST have been of great importance. Added to that, the group is also involved in studies using Chandra in X-rays and FUSE in the far-UV. These observations cover a broad range of instrumentation and wavelength regions. Much of the supernova modeling at the observatory is also closely related to these observations. We still have a large interest in the famous SN 1987A in the Large Magellanic Cloud, but recent research interests in the group cover also a a wider area of topics like supernova remnants, pulsars, supernova statistics, radiation processes, the gamma-ray burst connection and circumstellar interaction in supernovae. We are also involved in using thermonuclear supernovae for cosmology, and in constraining the nature of the progenitor systems for such supernovae. Part of the work is to study systematic effects in current and future supernova observations aiming at mapping the expansion history of the universe and thus gaining knowledge on the nature of the dark energy component. It also includes the study of methods to investigate, e.g., the dark matter distribution and current expansion velocity of the universe by looking at gravitationally lensed SNe with multiple images. The group is also actively participating in the SNAP project, a 2-metre telescope dedicated to observe light curves and spectra of more than 2000 SNIa per year as well as observing dark matter via weak gravitational lensing and providing ample high quality data for auxiliary science.

Figure 4. A false colour image of the blue compact galaxy ESO 338– 04 made from HST/ACS images. Red shows Hα, green shows far UV continuum and blue shows Lyα. 12

4.5. Galaxies and Cosmology (A. Adamo, J. Blasco Herrera, M. Blomqvist, K. Fathi, C. Fransson, M. Hayes, R. Karlsson, P.O. Lindblad, J. Melinder, G. Mellema, L. Mencia- Trinchant, G. Micheva, E. Mörtsell, M. Näslund, T. Riehm, Aa. Sandqvist, J. Sollerman, G. Ostlin¨ ) The research stretches from the centre of our Galaxy to the end of the ”dark ages” when the first stars and galaxies in the Universe turned on. Topics under study are:

(i) Observations and modelling of the dynamics and nuclear activity of spiral galaxies, including the Galactic Centre. We have expertise in using integral ﬁeld spectroscopy, and have been part of developing the GHAFAS Fabry-Perot interferometer for the WHT Telescope on La Palma. The group has also been actively involved in several programmes on the ODIN satellite. (ii) Starburst dwarf galaxies, e.g. blue compact galaxies, which are ideal labo- ratories for studying galaxy formation and evolution processes. We work on kinematics and star formation histories using data from ESO, NOT and HST. Another area of research is the anomalous red haloes found in BCGs and other galaxies. (iii) We have developed models for predicting the rates of diﬀerent types of supernovae as a function of the cosmic star formation rate. A large programme aimed at detecting more than 50 high redshift SNe has been performed using the VIMOS instrument at the ESO VLT, and we are active with the analysis. (iv) The process of reionisation will be studied at radio wavelengths in the near future with the LOFAR interferometer, and in preparation for this, large scale simulations of the reionisation process are performed using state of the art simulation tools. (v) The group is active in observations of Lyα and Lyman continuum escape from galaxies. We are using the HST to perform the most extensive imaging study of Lyα in nearby starbursts as yet, with the goal to better understand the physics regulating Lyα escape from galaxies. (vi) In collaboration with the CoPS group at the Department of Physics, Stockholm University, we are investigating the dark matter distribution on both small and large scales with the help of gravitational lensing. Furthermore, we explore the nature of dark energy, mainly by the use of type Ia supernovae. 13

4.6. High Energy Astrophysics (M. Axelsson, M. Battelino, L. Borgonovo, O. Engdeg˚ard, J. Trier Frederiksen, L. Hjalmarsdotter, A.˚ Höglund, S. Larsson, A. Meszaros, F. Ryde) The high energy astrophysics group specializes in observational/theoretical high energy astrophysics with emphasis on radiation processes in high energy plasmas in compact objects. We interpret broad band observations of active galactic nuclei (AGN), X-ray binaries (XRB), X-ray pulsars, and γ-ray bursts (GRB). Most observations are space-based (CGRO, RXTE, INTEGRAL, and future GLAST and PoGOLite). Archival data are extensively used. We are members of the Swedish GLAST (launch in May 2008) consortium and take an active part in the GRB and AGN science working groups. In collaboration with the astroparticle physics group at KTH and groups in USA and Japan we are preparing a hard X-ray polarimetry mission, PoGOLite. Such observations have so far been essentially unexplored, and in preparation for the PoGOLite mission we have in 2007 continued our simulations to study the instrument sensitivity and effects of particle and radiation background. We have made systematic studies of the X-ray variability pattern of the black hole candidate Cygnus X-1. Studies have also been made of the long term X-ray temporal and spectral variability of Cygnus X-1 as well as Cygnus X-3, also a black hole candidate. In addition, the temporal and spectral properties of the GRB prompt emission, e.g., of individual pulses, are studied in a long term program to uncover the physics of GRB. An intensive effort has been launched to study and analyse Swift data. Working contact with the Swift team at Penn State University has been established. On the theoretical and numerical side, the group is involved in modeling of GRB physics – specifically the prompt and afterglow phases. More generally, the group studies collisionless, radiative, highly relativistic outflows and shocks using fully kinetic modeling of plasmas in high-performance parallel computing environments. The group’s expertise falls within particle-in-cell modeling.

Figure 5. Montage of power spectra showing the fast X-ray variability of the galactic black hole binary Cygnus X-1. The sequence shows the full evolution from hard state (upper left panel) to soft state (lower right panel) of the source. The power spectra are from the systematic study of the source by the high-energy astrophysics group, which led to the ﬁrst ever complete tracking of the power spectral evolution of Cygnus X-1. 14

4.7. The Sun (J. de la Cruz Rodriguez, T. Hillberg, V. de Jorge Henriques, D. Kiselman, M. Löfdahl, G. Narayan, M. van Noort, G. Scharmer) The Institute for Solar Physics of the Royal Swedish Academy of Sciences [Kungl. Vetenskapsakademiens institut för solfysik] operates a solar observatory on the island of La Palma in the Spanish Canary islands. The research in solar physics takes advantage of the superb observing site to study small-scale solar phenomena such as granulation, sunspot structure, and small magnetic elements. The Swedish 1-m Solar Telescope (SST) is a world-leading high-resolution solar telescope and this season we accommodated about 20 visiting observers from 7 countries. The telescope routinely produces near-diffraction limited images, i.e., close to 0′′. 1 resolution in the blue part of the spectrum. Among the results based on SST data presented this year we note continued work on dark cored penumbral filaments, both observational and in modeling (see Fig. 6).

Figure 6. Sample photospheric intensity snapshot from MHD sunspot model. Note spontaneously appearing penumbra-like dark-cored ﬁlaments.

Important for our sub-arcsecond resolution ability is the in-house development of techniques for imaging, spectroscopy, polarimetry, wavefront sensing, adaptive op- tics, and image restoration, as well as instrumentation provided by our international partners. New instrumentation for this season was centered on the development and testing of the new double Fabry–Pérot instrument that will be installed in 2008 and used for imaging polarimetry, as well as on the new instrument control software needed to reliably operate new and old instruments at high data rates. The subjects of studies performed in the group include photospheric line-formation processes aimed at improving abundance analysis work, modeling of diagnostics for sunspot structure and dynamics including the Evershed effect in the penumbra. We are part of the USO-SP (Utrecht–Stockholm–Oslo Solar Physics) Interna- tional Graduate School is an Early Stage Training-project funded by the European Commission within its Marie Curie programme. It formalizes an ongoing collaboration between three solar physics institutes, aimed at combining their scientific strengths. We participate in the planning for future solar telescopes, both in space (Solar Orbiter) and on the ground (ATST and EST). 15

5. ACTIVITIES FOR THE GENERAL PUBLIC AND SCHOOLS

Stockholm Observatory provides open telephone lines (Gösta Gahm and Göran Olof- sson) for questions from the general public, and staff members are available for con- sultation by secondary and high school students. The news column on our web site (www.astro.su.se) was maintained by Michael Blomqvist and Teresa Riehm. The new telescope was installed in the dome on October 31. The telescope has a primary-mirror diameter of 1 meter and a focal length of 11 meters, and is a joint project of the Department of Astronomy and the Section of Chemical Physics at the Department of Physics at KTH. A press release made by the PR group attracted national and local TV and radio stations, as well as newspapers, to this happening. The telescope will mainly be used for research, but on special occasions the public will be invited. In March 2007 AlbaNova invited the public to an open house together with Vetenskapens hus. Several researchers from Stockholm Observatory gave lectures and observations were performed with the old 14” telescope. April 10th, 2007, Christer Fuglesang and the crew from the Discovery spacecraft met the public at Aula Magna. All 1200 seets were booked in advance and the event was broadcasted on the Stockholm University web-pages to acommodate the large interest. Several employees at Stockholm Observatory participated in the event which was hosted by Göran Ostlin.¨ Stockholm Observatory hosts the editorial staff of Populär Astronomi since July 2007. Several employees contribute material to the paper (see Sect. 7.1). Robert Cumming (Editor-in-Chief), Kambiz Fathi, and Anders Jerkstrand write a blog on the website of Populär Astronomi; www.popast.nu. Gösta Gahm is together with Nils Brenning at the Royal Technical Institute co-ordinating the project Sweden Solar System (SSS). SSS is by its geographical ex- tension the world largest model of our solar system (see www.astro.su.se/swesolsyst). In December 2007 a new model, of the newly discovered dwarf planet Eris, was in- augurated in Ume˚aat the science centre Umevatoriet. Stockholm Observatory has an intimate relationship with COSMONOVA, the Planetarium/Omnitheatre located at the Swedish National Museum of Natural His- tory in Stockholm. Aage Sandqvist has been the astronomical consultant to Cos- monova since 1972, vice-chairman of the Swedish Omnitheatre (Cosmonova) Foun- dation since 1991. As a token of appreciation of his continuing efforts, Cosmonova is placed at the disposal of the Stockholm Observatory twice a year, and free of charge, for presentations of astronomical programs to astronomy students at Stock- holm University and Saltsjöbadens Samskola. Staff members and PhD students have also participated in a number of presentations for the general public and schools, appeared on TV, radio and in the press. Only a few examples are listed here. Tanja Nymark Kramer participated in Universitetets Forskardagar (Stockholm University Research Days) with two lectures on her PhD thesis. Anita Sundman participated in a public discussion on the subject ”Ut i rymden” at Stockholms Akademiska Forum, 8 November 2007. Jesper Sollerman gave a lecture at Forskning och Framstegs Kunskapskryssning and appeared on national radio (Bildningsbyr˚an). Skolastro (Magnus Näslund) participated in some school activities, such as ”Den levande fr˚agel˚adan”, and continued to collaborate with Vetenskapens hus. Jens Melinder appeared on Nyhetsmorgon, TV4, and Göran Ostlin¨ participated regularly in Hjärnkontoret, SVT. 16

6. SEMINARS

Normally seminars were held on Fridays at 10:15 in 2007. The seminar organizers were Garrelt Mellema, Kay Justtanont (spring 2007) and Alexis Brandeker (fall 2007).

January 26, Planetesimal formation in turbulent protoplanetary discs Anders Johansen, Max-Planck-Institut für Astronomie, Heidelberg, Germany February 2, The Solar cycle: modeling and predicting Petri Käpylä, NORDITA, Stockholm, Sweden February 9, Planet Migration in non-isothermal Disks Sijme-jan Paardekooper, DAMTP, University of Cambridge, UK February 16, A Cosmic Hide-and-seek: The Chemical Remains of the First Stars Torgny Karlsson, NORDITA, Stockholm, Sweden February 23, Modelling Stelllar Clusters Ross Church, Lund Observatory, Sweden March 2, Inelastic Atomic Processes in Stellar Atmospheres: A Key to Understand- ing Stars, the Galaxy and the History of the Chemical Elements Paul Barklem, Dept. of Astronomy and Space Physics, Uppsala, Sweden March 16, Hercules stream stars and the metal-rich tail of the Galactic thick disk Thomas Bensby Dept. of Astronomy, University of Michigan, USA March 21, Evidence for efficient cosmic ray acceleration by supernova remnants Jacco Vink Dept. of Astronomy, Utrecht University, the Netherlands March 30, Supercritical accretion disk in SS433 and ultraluminous X-ray sources Sergei Fabrika Special Astronomical Observatory, Russia April 18, Gamma-ray bursts-progenitors and probes Andrew Levan University of Warwick, UK April 20, Methanol masers to study high-mass star formation Michele Pestalozzi University of Hertfordshire, University of Warwick, UK May 14, Simulating Cosmic Reionization: Character, Observability and Feedback on Galaxy Formation Ilian Iliev CITA, Toronto, Canada May 15, High-Energy Astrophysics Overview Gerald Fishman Nasa-Marshall Space Flight Center, USA May 25, Lyman-alpha emission: from local starbursts to cosmological populations Matthew Hayes Stockholm Observatory June 1, Mapping Ices on 1000 AU Scales in Pre-Stellar Cores Helen Fraser University of Strathclyde, Glasgow, UK June 15, A Heretic’s Approach to Solar System Formation Alan P. Boss Carnegie Institution of Washington, USA September 7, The centenary of the Blazhko effect: Is the solution in sight? Katrien Kolenberg Institute of Astronomy, University of Vienna, Austria September 20, The properties of intensely star-forming galaxies 1 Gyr after the Big Bang Matthew Lehnert Observatoire Paris-Meudon, France October 5, ”M” for ”Mystery”: What drives the winds of M-type AGB stars? Susanne Höfner Uppsala Astronomical Observatory, Sweden 17

October 12, New Results Concerning the Local Interstellar Medium: Structure, Dynamics, and Radio Scintillation Jeﬀ Linsky JILA, University of Colorado, USA October 19, Active galaxies: supermassive black holes and variability Margrethe Wold Inst. for Theor. Astrophys., University of Oslo, Norway November 9, The value of physical detail and numerical precision: How do steady dust-driven winds form? Christer Sandin AIP, Potsdam, Germany November 16, Stellar Collisions in the Galactic Centre Jim Dale Lund Observatory, Sweden November 30, Gaia-physical parameters for one billion stars Ulrike Heiter Uppsala Astronomical Observatory, Sweden December 7, How do core-collapse supernovae explode? Hans-Thomas Janka Max-Plank-Institute f¨ur extraterrestrische Physik, Garching December 14, X-ray light curve inversion of ultracompact binaries Pasi Hakala Tuorla Observatory, Turku, Finland 18

7. LIST OF PUBLICATIONS

Since 2007 all results published by researchers or other employees of Stockholm Uni- versity are gathered in the On-line Publication Documentation System for Stockholm University (OPUS). A list of most publications by researchers or other employees of Stockholm Observatory (Department of Astronomy) during 2007 can be found by visiting http://www.diva-portal.org/su/opus/ and entering only the year and the department. An alternative way of ﬁnding publications by employees of Stock- holm Observatory is to search the SAO/NASA Astrophysics Data System (ADS) at http://www.adsabs.harvard.edu/. A list of popular science publications can be found below.

7.1. Popular Science Publications 1. Gahm, G. F., 2007, F˚ar jorden en framsida och baksida?, Forskning och Framsteg, nr. 4, 2007, 67 2. Gahm, G. F., 2007, Hur vet man var stjärnorna är?, In the book Dricker fiskar vatten?, ed. Björn Fjæstad, bokförlaget DN, p. 18 3. Kiselman, D. and Lundqvist, S., 2007, Utsikt fr˚an jorden 19: Det bara händer, Populär astronomi, nr. 2, p. 39 4. Kiselman, D. and Lundqvist, S., 2007, Utsikt fr˚an jorden 20: Longitud, Populär astronomi, nr. 3, p. 46 5. Kiselman, D. and Lundqvist, S., 2007, Utsikt fr˚an jorden 21: Lik en diamant i skyn, Populär astronomi, nr. 4, p. 50 6. Nymark Kramer, T., 2007, Stjärnstoft ska du˚ater bli, Kemivärlden Biotech, nr. 7/8, August 2007 7. Näslund M., 2007, Ta hissen till teleskopet - drömmen om ett eget skolobser- vatorium blev verklighet, Populär Astronomi, nr. 1, p. 44 8. Näslund M., 2007, Unga astronomistuderande flyttar in i observatoriet i Salt- sjbaden, Populär Astronomi, nr. 2, p. 44 9. Näslund M., Blomqvist A., 2007, Fuglesang med kamrater besökte Stockholms universitet, Populär Astronomi, nr. 2, p. 45 10. Näslund M., 2007, Mäta tid - ett projekt för mellanstadiet, Populär As- tronomi, nr. 3, p. 44 11. Sandqvist, Aa., 2007, COSMONOVA och Odin, en personlig ˚aterblick, Den Svenska Almanackan 2008, p. 132 12. Sandqvist, Aa., 2007, Vilka förmörkelser är vanligast?, Forskning och Fram- steg, nr. 2, 2007, p. 59 13. Pedersen, K., Andersen, A., Fynbo, J., Hansen, S., Hjort, J., Sollerman, J., and Watson, D., 2007, Jagten p˚adet mørke stof, Naturens Verden, nr. 9, p. 2 14. Andersen, A., Fynbo, J., Hansen, S., Hjort, J., Pedersen, K., Sollerman, J., and Watson, D., 2007, Kosmisk støv, Naturens Verden, nr. 11/12, p. 53 19

15. Sollerman, J., 2007, Supernova 1987A fyller 20 ˚ar, Forskning och Framsteg, nr. 1, 2007, p. 46 16. Sollerman, J., 2007, Det hände 160 000 ˚ar tidigare, Forskning och Framsteg, nr. 4, 2007, p. 66 17. Sundman, A., 2007, Tankens bilder av kosmos, Forskning och Framsteg, nr. 8, 2007, p. 21 18. Sundman, A., 2007, Krönika, Populär Astronomi, nr. 1, 2007, p. 31 19. Sundman, A., 2007, Krönika, Populär Astronomi, nr. 3, 2007, p. 31

7.2. The Swedish Almanac [Den Svenska Almanackan] The Swedish Almanac [Den Svenska Almanackan] is the oﬃcial astronomical almanac in Sweden, with roots going back to the sixteenth century. From 1749 to 1972, it was published with exclusive almanac rights by the Royal Swedish Academy of Sciences (KVA). Subsequently, it has been published by Esselte Almanacksforlag (now known as Almanacksf¨orlaget) in collaboration with Stockholm Observatory. Its editor since 2006 is Cecilia Kozma. A simpler, but much more widely distributed, version of this almanac (Vanliga Almanackan) contains in addition a considerable amount of non-astronomical matter, but the astronomical part of the latter almanac is also produced in collaboration with the Stockholm Observatory. The editor for the astronomical part of this almanac since 2006 is also Cecilia Kozma.

1. Den Svenska Almanackan 2008, 2007, ed. C. Kozma, Almanacksf¨orlaget, Stockholm, 160 pages 2. Vanliga Almanackan 2008, 2007, eds. C. Kozma, K. Wiberg, Almanacksf¨orlaget, Stockholm, 80 pages 20

8. STAFF

Positions are financed by the Stockholm University and/or by the following external financial sources: ESMN - European Solar Magnetometry Network, EU RTN - European Union Network, HS - House of Science [Vetenskapshuset], NOTSA - Nordic Optical Telescope Scientific Association, SNSB - Swedish National Space Board [Rymdstyrelsen], USO-SP - Utrecht-Stockholm-Oslo international graduate school for Solar Physics (EC), VR - Swedish Research Council [Vetenskapsr˚adet], the Wenner-Gren foundations, Almanacksförlaget, KVA – The Royal Swedish Academy of Sciences [Kungliga Vetenskapsakademien]. A relation to the Institute for Solar Physics (ISP) is indicated below.

8.1. Faculty Björnsson, Claes-Ingvar: Associate Professor, Director Cumming, Robert: Researcher Fransson, Claes: Professor Gahm, Gösta: Professor Justtanont Liseau, Kay: Research Scientist (until 070815) Kiselman, Dan: Research Associate (ISP) Kozma, Cecilia: Researcher (30 %) Thébault, Philippe: Guest Researcher Larsson, Bengt: Research Scientist Larsson, Stefan: Research Scientist Lindblad, Per Olof: Professor Emeritus Liseau, René: Professor (until 070815) Lundqvist, Peter: Professor Löfdahl, Mats: Research Associate (ISP) Mellema, Garrelt: Associate Professor Mörtsell, Edvard: Research Associate Näslund, Magnus: School-project leader, Lecturer (from 071201) Olofsson, Göran: Professor, Deputy Director Olofsson, Hans: Professor (20 %) Ryde, Felix: Research Associate Sandqvist, Aage: Professor Emeritus Scharmer, Göran: Professor (ISP) Schober, Jan: Research Scientist Schöier, Fredrik: Research Associate (until 070630) Sollerman, Jesper: Research Associate (20 %) Sundman, Anita: University Lecturer Ostlin,¨ Göran: Associate Professor

8.2. Postdoctoral Fellows Fathi, Kambiz: (50 %) van Noort, Michiel: (ISP) (until 070506) 21

8.3. Technical Staff Florén, Hans-Gustav: Research Engineer Gelato, Sergio: System Manager van Noort, Michiel: Research Engineer (ISP) (from 0707) Wänn, Uno: Research Engineer (60 %)

8.4. Administrative Staff Engberg, Ulla: Secretary, student office (80 %) Olofsson, Lena: Senior Administrative Officer Aberg,˚ Sandra: Personnel adm.

8.5. Graduate Students In many cases, graduate students receive full-time economic support from Stockholm Observatory: 80% as a study grant [utbildningsbidrag] or a graduate studentship [doktorandtj¨anst] and 20% as a teaching assistant position. The latter may also include administrative duties in addition to teaching duties. In some cases students are partially supported as Research Assistants by research grants from the research councils (VR, RS, KVA), or international organizations (EU, NOTSA).

Adamo, Angela Axelsson, Magnus (undergraduate student advisor) Banhidi, Zita Blasco Herrera, Javier (from 070913) Blomqvist, Michael Borgonovo, Luis (until 0705) de la Cruz Rodriguez, Jaime (ISP, USO-SP) Dimoudi, Sofia: Marie-Curie Trainee (ISP, USO-SP) (2007-01-15–2007-07-14) Elfhag, Torsten Friedrich, Martina (from 070510) Grigorieva, Anna Gröningsson, Per G˚alfalk, Magnus Hayes, Matthew (until 0709) Hillberg, Tomas (ISP) Hjalmarsdotter, Linnea (Helsinki University) Hniopek, Kristoffer (until 070601) Jerkstrand, Anders de Jorge Henriques, Vasco (ISP, USO-SP) (from 070501) Karlsson, Roland Kuutmann, Andrej (from 070913) Lundqvist, Natalia Maercker, Matthias Melinder, Jens Mencia Trinchant, Laia Micheva, Genoveva Narayan, Gautam (ISP) Nilsson, Ricky Nymark, Tanja (until 070630) Olofsson, Sven 22

Peplinski, Adam Pereira, Tiago: Marie-Curie Trainee (ISP, USO-SP) (2007-04-01–2007-06-30) Ramstedt, Soﬁa Riehm, Teresa Trier Frederiksen, Jakob de Val Borro, Miguel

8.6. Board of the Observatory The board consists of regular members, and deputy members who may substitute when regular members are unable to participate. The present board consists of the Director, the Deputy director, three representatives (with three deputies) from the faculty, one representative (with deputy) from the technical/administrative (T/A) group, two representatives (with one deputy) from the graduate students, and one representative (with deputy) from the undergraduate students (the graduate and undergraduate student representatives are elected on a one year basis).

Claes-Ingvar Björnsson (director) Göran Olofsson (deputy director) Dan Kiselman (faculty repr.) RenéLiseau (faculty repr. until 070815) Göran Ostlin¨ (faculty repr.) Claes Fransson (1st deputy faculty repr.) Felix Ryde (2nd deputy faculty repr.) Kay Justtanont Liseau (3rd deputy faculty repr. until 070815) Sandra Aberg˚ (T/A repr.) Sergio Gelato (deputy T/A repr.) Sofia Ramstedt (grad. stud. repr.) Matthias Maercker (grad. stud. repr.) Michael Blomqvist (deputy grad. stud. repr.) Teresa Riehm (deputy grad. stud. repr.) Magnus Persson (undergr. stud. repr.) Martin Lindman (deputy undergr. stud. repr.) 23

9. COMMITTEE MEMBERSHIPS

Faculty members are often involved in the work of national or international committees. The membership list presented here is not complete, but gives an indication of the role played by the faculty in national and international committees.

Kambiz Fathi: International – Member of the Science council for the 3DNTT instrument to be mounted at the NTT telescope in Chile. Member of the Eu- ropean Astronomical Society. Member of the American Astronomical Society. Member of the Cambridge University Astronomical Society. Claes Fransson: National – Member of the Royal Swedish Academy of Sciences. Member of the Crafoord prize committee for astronomy. Member of the Swedish National Committee for Astronomy. Vice chairman of the Swedish Research Council Particle Physics and Astrophysics Committee. Member of the Committee for Research Infrastructures of the Swedish research Council (KFI). Vice chairman of the Subcommittee for subatomic physics and and astronomy of KFI; International – Member of ESO Council. Member of ESO Strategy Working Group. Member of ”Fachbeirat der Max-Planck-Institut für Astrophysik” in Garching. Member of Nordita astrophysics committee. Member of the SWG of ASTRONET Science Vision and Co-chair of the panel for ’Extremes of the Universe’. Member of the organizing committees for several conferences. Gösta Gahm: National – Chairman of the Swedish Astronomical Society and of the related Planetarium Foundation and Editorial Board of Populär Astronomi. Member of the national reference group for planning the International Year of Astronomy 2009. International – Member of the ESO Observing Programme Committee. Deputy member of the ESO-outreach committee. Kay Justtanont: International – Member of the IAU commission 34 (interstellar medium). Sweden/Ireland project manager for the JWST/MIRI project. Member of Herschel/HIFI guaranteed time consortium. Dan Kiselman: National – Secretary of the Swedish Astronomical Society; Member of the Swedish National Committee for Astronomy; International – Member of the Financial Sub Committee of the International Scientific Committee for the observatories of the Instituto de Astrof´ısica de Canarias. Per Olof Lindblad: National – Member of the Royal Swedish Academy of Sci- ences; International – Member of the General Prize Committee of the Balzan Foundation. Foreign member of the Norwegian Academy of Science and Let- ters. RenéLiseau: National – Member/chair of The Scientific Reference Group (SRG) to the National Space Board (SNSB). Secretary of the Swedish National Com- mittee for Astronomy. Chair of the APEX/OSO Observing Time Allocation Committee; International – Swedish Lead Co-I of the Herschel/HIFI consortium and member of the HIFI Steering Committee. Member of the TE-SAT (Darwin scientific advisory team to ESA). Member of the TPF-SWG (Ter- restial Planet Finder of NASA, Scientific Working Group). Consultant to SPIRE Specialist Astronomy Group. Member of the Astronomy Working Group (ESA). Lead CoI of the Odin Astronomical Team. Member of the American Astronomical Society. Peter Lundqvist: National – Member of the ”Matematisk-fysiska sektionsbered- ningen” at Stockholm University; International – Swedish representative in IAU Commission 46. Proposal evaluations for Subaru. 24

Garrelt Mellema: International – SOC for Radiative Transfer workshop; Septem- ber 3-7, 2007, Durham. Member of the LOFAR Epoch of Reionization Key Project. Göran Olofsson: International – Co-I and member of the steering committee for Herschel/SPIRE. Co-PI of the European JWST/MIRI consortium. Swedish Co-I and member of the steering committee of Herschel/SPIRE. PI of the Herschel Guaranteed Time proposal on stellar disks. Member of the ESO Science Technical Committee. Member of ESO/ESE (E-ELT Science & En- gineering Working Group). Hans Olofsson: National – Member of the Royal Swedish Academy of Sciences, Member of the Royal Society of Sciences (Uppsala). Member of the Swedish National Committee for Astronomy. Director of the Swedish National Facility for Radio Astronomy, Onsala Space Observatory, Chalmers Univ. of Tech- nology, Gothenburg. Guest professor in radio astronomy, Chalmers Univ. of Technology, Gothenburg. Aage Sandqvist: National – Vice-Chairman of the Swedish Omnitheatre (Cos- monova) Foundation. International – Lead CoI of the Odin Galactic Centre Astronomical Team. Member of the Herschel/HOP consortium. Göran Scharmer: National – Member of the Royal Swedish Academy of Sci- ences; International – Member of the International Scientific Committee for the observatories of the Instituto de Astrof´ısica de Canarias; Member of the Norwegian Academy for Science and Letters. Jesper Sollerman: National – Member of the editorial Board of Populär As- tronomi; International – Swedish member of the Astronomy & Astrophysics Journal Board of Directors. Member of the Nordic Optical Telescope Observ- ing Programme Committee. Swedish member of the ESO Outreach Network. Göran Ostlin¨ : National – Chair of the evaluation committee of sub-atomic physics and astrophysics (’beredningsgrupp i subatomär fysik och astrofysik’) of the Swedish Research Council. Member of the Manne Siegbahn Memorial Lec- ture Committee. Member of the Swedish National Commitee for Astronomy; International – Member of the Swedish JWST/MIRI consortium. Member of the European Space Agency’s Astronomy Working Group (ESA-AWG).