Title: KROSS: The KMOS Redshift One Spectroscopic Survey

　　Speaker：Prof. Martin Bureau (University of Oxford)

　　Short biographical introduction：

　　Martin Bureau is a self-described galaxy guru, with an interest in anything and everything galactic. He is particularly interested in using observations and theoretical studies of the gas, stars, and dark matter that make up galaxies to constrain their formation and evolution.

　　Martin is Professor of Astrophysics at the University of Oxford, and Lindemann Fellow and Tutor in Physics at Wadham College. He has been in Oxford for over a decade, following appointments at Columbia University as a NASA Hubble Fellow and at Leiden University. He obtained his PhD from The Australian National University and is originally from Montreal, Canada.

　　Abstract：I will present results from the KMOS Redshift One Spectroscopic Survey　(KROSS). Using the K-band Multi-object Spectrograph (KMOS) at the Very　Large Telescope (VLT), KROSS has gathered integral-field data for ~800　star-forming galaxies at a redshift z~1, when the universe was roughly　half its current age and forming the bulk of its stars. KROSS aims to　study the spatially-resolved dynamics, star formation properties and　metallicities of those middle-aged galaxies. First, I will quantify　the dynamical state of the galaxies, thus constraining their likely　mass growth mechanisms (e.g. mergers versus secular evolution),　painting a picture of galaxies that are both gas-rich and highly　turbulent. Second, I will describe the properties of the galaxies　departing from the star formation main sequence, revealing that star　formation in highly star-forming galaxies is also more concentrated　and arises from lower metallicity gas. Third, I will present the　observed and baryonic Tully-Fisher (luminosity - rotation velocity)　relation, thus constraining the mass-to-light ratios and luminous+dark　masses of the galaxies. Last, by degrading and analogously analysing　integral-field data of hundreds of local galaxies from the Sydney-AAO　Multi-object Integral-field Spectrograph (SAMI) survey, I will derive　a comparison Tully-Fisher relation at z=0, thus constraining the　luminous+dark mass growth of disk galaxies over the last 7 billions　years. This unique comparison also highlights that the systematic　effects associated with sample selection and analysis methods are as large as the effects expected from cosmological evolution, and thus that most other results can safely be ignored.

　　Time：10 April (Monday), 10:00am

　　Place：402 Room, Astronomy Building

欢迎各位老师、同学参加！

　　                                           南京大学天文与空间科学学院