题 目： The formation of the disk in grand-design spirals

报告人：Prof. Francois Hammer

（Laboratoire Galaxies étoiles Physique et Instrumentation, Observatoire de Paris）

摘 要:

The flatness of the rotation curve inside spiral galaxies is interpreted as the imprint of an halo of invisible matter. Using the deepest observations of distant galaxies, we have investigated how large disks could have been formed. Observations include spatially-resolved kinematics, detailed morphologies and photometry from UV to mid-IR. Six Giga-years ago, half of the present-day spirals were experiencing major mergers, evidenced by their anomalous kinematics and morphologies. A considerable fraction of their stars have been formed during these events that lead to a disk rebuilding after a major collision. I will present the evolution of the Tully Fisher relation (velocity versus mass) and show how it evolves during the last eight Gyrs.

时 间：2009年7月17日上午10:30

地 点：（北京西路2号）紫台大楼327教室

紫金山天文台学术委员会学术交流工作委员会

2009年7月9日