Research Institute Leiden Observatory (Onderzoekinstituut Sterrewacht Leiden) Annual Report Sterrewacht Leiden Faculty of Mathematics and Natural Sciences Leiden University Niels Bohrweg 2 Postbus 9513 2333 CA Leiden 2300 RA Leiden The Netherlands http://www.strw.leidenuniv.nl An electronic version of this annual report is available on the web at http://www.strw.leidenuniv.nl/research/annualreport.php Production Annual Report 2013: E. Gerstel, A.S. Abdullah, N. Lopez-Gonzaga, I. Snellen, F. Mernier, H.J.A. R¨ottgering,D. Klaassen ii STERREWACHT LEIDEN Excecutive (Directie Onderzoeksinstituut) Director H.J.A. Rottgering¨ Directeur Director of Studies P.P. v.d.Werf Opleidings Directeur Institute Manager E. Gerstel Instituutsmanager Supervisory Council (Raad van advies) Prof. Dr. Ir. J.A.M. Bleeker (Chair) Dr. B. Baud Drs. J.F. van Duyne Prof. Dr. K. Gaemers Prof. Dr. C. Waelkens iii Contents 1 Review of major events 1 2 Research 9 2.1 Solar system .............................. 9 2.1.1 14N/15N detectability in Pluto’s atmosphere ......... 9 2.2 Proto-planetary disks and exoplanets ................ 9 2.2.1 Direct imaging of extrasolar planets ............. 9 2.2.2 New type of telescope may detect extraterrestrial life .... 10 2.2.3 Novel technique boosts hunt for water on exoplanets .... 12 2.2.4 Studying planet formation with AMUSE ........... 12 2.2.5 Discovery of a major asymmetric dust trap in a transitional disk ............................... 14 2.2.6 Tracing the CO snowline in disks with N2H+ and DCO+ .. 15 2.2.7 Far-infrared line survey of disks ................ 17 2.3 Protostars ............................... 18 2.3.1 Water in star-forming regions with Herschel (WISH) .... 18 2.3.2 Where has all the O2 gone in low-mass protostars? ..... 19 2.3.3 Modeling disk formation .................... 20 2.3.4 Detection of the youngest rotationally supported disk with ALMA ............................. 20 2.3.5 Probing high-mass star-formation with masers ........ 21 2.4 Stars and compact objects ...................... 21 2.4.1 GAIA .............................. 21 2.4.2 The fast evolution of the variable yellow hypergiant HR5171A 22 2.4.3 Surprising detection of an equatorial dust lane on the AGB star IRC+10216 ........................ 23 2.5 The Milky Way and nearby galaxies ................. 25 2.5.1 Probing interstellar turbulence with LOFAR ......... 25 2.5.2 High-velocity stars and the dark-matter halo ........ 26 2.5.3 Galactic Interstellar Medium ................. 27 2.5.4 Nearby starburst galaxies ................... 28 2.6 Distant galaxies and clusters ..................... 28 v CONTENTS 2.6.1 Studying galaxy gass-masses with the Sloan Digital Sky Survey ............................. 28 2.6.2 (Ultra)luminous infrared galaxies ............... 29 2.6.3 High redshift submillimetre galaxies ............. 30 2.6.4 The host galaxy of the z = 2.4 radio-loud AGN MRC 0406244 as seen by HST ......................... 31 2.6.5 Shocks in merging clusters of galaxies ............ 32 2.6.6 The most distant galaxies ................... 33 2.6.7 Studying galaxy and cluster evolution using weak lensing . 33 2.6.8 Tracing the emergence of large scale structure with high- redshift proto-clusters ..................... 34 2.7 Theoretical studies of galaxies and large scale structure ...... 35 2.7.1 Physical properties of simulated galaxy populations at z = 2 35 2.7.2 Non-equilibirum ionization and cooling of metal-enriched gas in the presence of a photoionization background .... 36 2.7.3 AGN proximity zone fossils and the delayed recombination of metal lines .......................... 36 2.7.4 A measurement of galaxy halo mass from the surrounding H I Lyα absorption ...................... 37 2.7.5 On the evolution of the H I column density distribution in cosmological simulations .................... 37 2.7.6 Soft X-ray and ultraviolet metal-line emission from the gas around galaxies ......................... 38 2.7.7 Stellar radiation feedback in galaxies ............. 38 2.8 The Raymond and Beverly Sackler Laboratory for Astrophysics .. 40 2.8.1 N2 photodissociation finally unravelled ............ 41 2.8.2 Effects of reagent rotation and vibration on reactions .... 42 2.8.3 From PAHs, to graphene: Destroying PAHs in space, one hydrogen at a time ....................... 42 2.9 The iSPEX citizen science experiments ............... 42 2.10 AstroPAH Newsletter ......................... 45 3 Education, popularization and social events 49 3.1 Education ............................... 49 3.2 Degrees awarded in 2013 ....................... 51 3.2.1 Ph.D. degrees .......................... 51 3.2.2 Master degrees ......................... 54 3.2.3 Bachelor degrees ........................ 54 3.3 Academic courses and pre-university programmes ......... 55 3.3.1 Courses taught by Observatory staff ............. 55 3.3.2 Pre-university programme ................... 55 3.3.3 Contact.VWO ......................... 56 vi CONTENTS 3.4 Popularization and media contacts .................. 58 3.5 Universe Awareness programme ................... 63 3.5.1 Teacher training ........................ 63 3.5.2 Educational resources ..................... 63 3.5.3 International network ..................... 64 3.6 Astronomy for Development ..................... 64 3.7 The Leidsch Astronomisch Dispuut F. Kaiser ............ 65 3.8 Vereniging van Oud-Sterrewachters ................. 66 I Observatory staff 69 II Committee membership 77 II.1 Observatory Committees ....................... 77 II.2 University Committees (non-Observatory) .............. 80 III Science policy functions 85 IV Workshops, colloquia and lectures 95 IV.1 Workshops ............................... 95 IV.2 Endowed Lectures ........................... 98 IV.3 Scientific Colloquia .......................... 98 IV.4 Student Colloquia ...........................101 IV.5 Colloquia given outside Leiden ....................101 V Grants 113 VI Scientific publications 117 VI.1 Ph.D. Theses ..............................117 VI.2 Publications in refereed journals ...................118 VI.3 Publications in non-refereed journals .................161 VI.4 Popular Articles ............................186 vii Chapter 1 Review of major events Review of major events Chapter 1 As a proud member of Leiden Observatory, I am delighted to report that 2013 was again an excellent year for the observatory. Its mission remains to: carry out world-class astronomy research, maintain a strong PhD program, • help shape future large international observational facilities and develop key technologies for ground breaking astronomical discoveries, provide excellent education at the bachelor and master level, not only to • prepare students for PhD projects, but also for the general job market, and inform the general public of exciting results and the beauty of the Universe. • The research that we carry out covers a broad range and is well matched to the science networks of the national NOVA research school in which the astronomy institutes from Amsterdam, Groningen and Nijmegen partake. Our particular emphasis is on observational and theoretical studies of the formation and evolution of galax- • ies and the structures in which they are embedded exo-planets, star and planet formation. • The Sterrewacht has access to first class ground and space-based observational facilities around the world, hosts in-house optical and astrochemical laboratories, and has built dedicated large scale multi-processing computing facilities. A very important resource are the observational facilities that are provided by the European Southern Observatory (ESO). ESO is a major partner in ALMA, the large mm/submm radio telescope located in the Atacama desert in Chile, officially 1 Chapter 1. Foreword opened in 2013. Since 2009, Leiden Observatory hosts the Dutch ALMA regional science center ALLEGRO. Funded by NWO, ALLEGRO provides general face-to- face user support for the entire Dutch community. One of its focus points is to help plan and reduce high frequency observations, in particular those using the Dutch-built Band 9 receiver system. Leiden is also the PI institute for METIS, one of the first generation of instruments to be built for the next ESO large telescope project: the Extremely Large Telescope (ELT). In 2013, there were major achievements related to the three fold mission of the observatory as mentioned above: research, education and outreach. This annual report provides a comprehensive overview of all the activities in these areas. In this preface to the annual report, it is tempting to mention many of the exciting science results that we have produced last year. Instead I would like to refer the interested reader to the first Chapter of this annual report and mention here only a few of the most exciting highlights. A major and still growing area of research is the study of exo-planets. About ten years ago there was virtually no activity in this field. Now Ignas Snellen, Matt Kenworthy and Christoph Keller spend a significant amount of their time explor- ing the often surprising properties of exo-planets. Possibly their most fascinating result of 2013 was the first detection of water in the atmosphere of an exo-planet. They studied HD 189733 system that hosts a rather weird exoplanet which orbits its star every 2.2 days and has a temperature of over 1500 degrees Celsius. The team led by Jayne Birkby and Ignas Snellen detected the spectral line of water in this exo-planet atmosphere using the CRyogenic high-resolution InfraRed Echelle Spectrograph (CRIRES)