Nova Report 2006-2007
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NOVA REPORTNOVA 2006 - 2007 NOVA REPORT 2006-2007 Illustration on the front cover The cover image shows a composite image of the supernova remnant Cassiopeia A (Cas A). This object is the brightest radio source in the sky, and has been created by a supernova explosion about 330 year ago. The star itself had a mass of around 20 times the mass of the sun, but by the time it exploded it must have lost most of the outer layers. The red and green colors in the image are obtained from a million second observation of Cas A with the Chandra X-ray Observatory. The blue image is obtained with the Very Large Array at a wavelength of 21.7 cm. The emission is caused by very high energy electrons swirling around in a magnetic field. The red image is based on the ratio of line emission of Si XIII over Mg XI, which brings out the bi-polar, jet-like, structure. The green image is the Si XIII line emission itself, showing that most X-ray emission comes from a shell of stellar debris. Faintly visible in green in the center is a point-like source, which is presumably the neutron star, created just prior to the supernova explosion. Image credits: Creation/compilation: Jacco Vink. The data were obtained from: NASA Chandra X-ray observatory and Very Large Array (downloaded from Astronomy Digital Image Library http://adil.ncsa.uiuc. edu). Related scientific publications: Hwang, Vink, et al., 2004, Astrophys. J. 615, L117; Helder and Vink, 2008, Astrophys. J. in press. Illustrations on the back cover Clockwise starting at upper left. 1. First light of the near-infrared arm of X-shooter in December 2007. A Th-Ar spectrum with wavelength running from below left (1000 nm) to top right (2500 nm) showing that the spectrograph is working properly (photo credit: Matthew Horrobin). 2. First MIRI verification model test results obtained in the cryo-vacuum chamber at RAL on 19 December 2007. The individual image slices are clearly seen. The strong fringing in the spectral (vertical) direction is well characterized and is being investigated by Lahuis and Martinez. 3. ALMA Band-9 receiver cartridges #3-8 tested and awaiting acceptance in August2007 (photo credit Ronald Hesper). 4. Suzanne Bisschop at work on SURFRESIDE, a NOVA funded laboratory project at the Raymond and Beverly Sackler Laboratory for Astrophysics, to study the formation of complex molecules in space, including the first production of alcohol ice under simulated interstellar conditions. NOVA Report 2006 - 2007 NOVA Report 2006 - 2007 NOVA Nederlandse Onderzoekschool voor de Astronomie Netherlands Research School for Astronomy Postal address P.O. Box 9513 2300 RA Leiden, The Netherlands Phone: +31 (0)71 527 5837 Fax: +31 (0)71 527 5743 E-mail: [email protected] Web: http://www.strw.leidenuniv.nl/nova Address J.H. Oort building Niels Bohrweg 2 2333 CA Leiden, The Netherlands Public outreach NOVA Information Center Web: http://www.astronomie.nl NOVA is a federation of the astronomical institutes at the universities of Amsterdam, Groningen, Leiden, Nijmegen and Utrecht, legally represented by the University of Groningen until 31 August 2007 and by the University of Utrecht from 1st September 2007. 2 NOVA Report 2006 - 2007 Table of contents 1. Introduction . 5 2. Mission statement and research program . 7 3. Progress reports from the research networks . 9 3.1. Formation and evolution of galaxies: from high redshift to the present . 9 3.2. Formation and evolution of stars and planetary systems . 30 3.3. Final stages of stellar evolution: physics of neutron stars and black holes . 49 4. PhD's in astronomy awarded in 2006 - 2007 . 76 5. Instrumentation program . 78 5.1. ALMA high-frequency prototype receiver . 78 5.2. Dutch Open Telescope (DOT) . 81 5.3. OmegaCAM . 83 5.4. Sackler Laboratory for Astrophysics . 85 5.5. JWST-MIRI . 87 5.6. Multi Unit Spectroscopic Explorer (MUSE) . 88 5.7. X-SHOOTER . 90 5.8. Spectro-Polarimetric Exoplanet Research (SPHERE) . 92 5.9. LOFAR for astronomy . 93 5.10. Photometric instrument algorithms for the Gaia mission . 96 5.11. Preparation Phase-3 instrumentation program . 98 5.12. Towards a NOVA optical-IR instrumentation group . 98 5.13. Preparations for the involvement in the E-ELT . 98 6. NOVA funded astronomical research . 101 7. Workshops and Visitors . 104 8. Public Outreach and Education . 117 8.1 NOVA Information Center(NIC) . .117 8.2 Astronomy Olympiad. 118 8.3 Education . 118 9. Organization . 120 10. Financial report 2006 - 2007 . 122 11. List of abbreviations . 123 3 NOVA Report 2006 - 2007 1. Introduction The ultimate goal of astronomical research is to understand the Universe and the objects within it in terms of the laws of physics. Questions concerning the nature and evolution of the Universe are profound and appeal to a deep human desire to understand our place in the Universe. They relate directly to such questions as the geometry of space time, the nature of dark matter and dark energy which constitute over 95% of the matter and energy in the universe but leave no direct trace, the formation of the elements, and ultimately, the origin of stars, planets, such as the Earth, and life itself. Furthermore, the Universe provides a unique laboratory for investigating the laws of physics and chemistry under conditions far more extreme than can be reached in a laboratory on Earth. Astrophysicists study phenomena involving enormous scales of time, length and mass (the entire Universe), huge densities (e.g., neutron stars, black holes), extreme vacua (interstellar and circum- stellar media), immense energies (explosive phenomena such as supernovae, quasars) and intense fluxes of particles and radiation (neutrinos, gamma ray bursts). The Netherlands Research School for Astronomy, NOVA, is one of the six national focus points of excellent research. They were selected by the Netherlands Organization for Scientific Research (NWO) from 34 proposals covering all academic disciplines. Funding started in 1999 under the so- called ‘In-Depth Strategy’ program initiated by the Ministry of Education, Culture and Science. In 2006 the minister decided to continue the funding for the six ‘top-research schools’ for the period 2009 – 2013 and to initiate a major program review in 2009- 2010 which could result in continua- tion of funding beyond 2013 if the excellent quality in comparison with the best foreign institutes in their field of research can be demonstrated. The central theme of the research carried out within NOVA is ‘The Life-Cycle of Stars and Galax- ies: from high-redshift to the present’. This requires full knowledge of many aspects of astronomy and astrophysics (see Chapter 3 for examples), and access to state-of-the-art observations. A key component of the NOVA program is therefore to build and develop new astronomical instruments and to carry out technical R&D for the next generation instruments (see Chapter 5). In the reporting period the NOVA program involved 270 fte scientific staff members spread over the five universities participating in NOVA. This number includes ~60 fte senior staff members in permanent and tenure-track positions, 40 fte postdoctoral fellows, 130 fte PhD students, and ~40 fte staff working on instrumentation projects. NOVA funds about 19% of these positions, as well as an active workshop and visitor program (see Chapter 7), and outreach efforts through the NOVA Information Center (see Chapter 8). The year 2007 saw the departure of Tim de Zeeuw, who had served as the founding Director of NOVA since 1992. He helped shape Dutch astronomy over many years, and had a key role in the development of the entire NOVA program. He accepted the challenging position of Director- General of ESO starting September 1 2007. A one day national symposium highlighting NOVA science over the last decade was held in his honor on August 27 2007. A number of other changes in the NOVA organization also occurred on September 1 2007: (1) transfer of the legal representation of NOVA from the University of Groningen, who had this task for five years, to the University of Utrecht; (2) van der Kruit stepped down as chair of the NOVA Board after holding this position for four years. He was succeeded by van der Klis; (3) van Dishoeck started as NOVA Scientific Director and Boland was promoted to Executive Director. The period 2006-2007 saw once again a rich variety of new astrophysical results which are sum- marized in Chapter 3. Highlights include discoveries of massive red galaxies in the early universe that stopped forming stars at a surprisingly young age (Kriek, Franx et al.), of a new class of tran- sitional protoplanetary disks with large inner dust holes still containing gases and PAHs (Geers, van Dishoeck et al.) and of the first transient Z-type low-mass X-ray binary (Homan, van der Klis, Wijnands et al.). Also, strong indications were found that our Milky Way did not form by a merger of dwarf satellite galaxies, contrary to popular formation theories (Helmi, Tolstoy, et al.), that the SNR RCW 86 was formed in the 185 AD supernova recorded in China (Vink et al.), and that the enigmatic supernova 2006gy resulted from a merger of two massive stars (Portegies Zwart & van 5 NOVA Report 2006 - 2007 den Heuvel). Ormel, Dominik and collaborators improved our understanding of grain growth and dust aggregation as the first steps toward planet formation; Mokiem, de Koter, Langer et al. determined the initial rotation rates of the most massive stars and subsequent evolution- ary consequences; and Falcke and his group participated in the first Pierre Auger Observatory results showing a correlation between high energy cosmic rays and Active Galactic Nuclei, and pursued complementary radio experiments.