Early-type galaxies, considered as large bulges, have been found to have had a much-more-than-boring star formation history in recent years by the UV satellite GALEX. The most massive bulges, brightest cluster galaxies, appear to be relatively free of young stars. But smaller bulges, normal ellipticals and lenticulars, often show unambiguous sign of recent star formation in their UV flux. The fraction of such UV-bright bulges in the volume-limited sample climbs up to the staggering 30%. The bulges of spirals follow similar trends but a larger fraction showing signs of current and recent star formation. The implication on the bulge formation and evolution is discussed.
|Number of pages||6|
|Journal||Proceedings of the International Astronomical Union|
|Publication status||Published - 2007 Jul|
Bibliographical noteFunding Information:
This review is based on many people’s hard work. Special thanks go to the GALEX science operation and data analysis team, Karl Forster, Mark Seibert, Todd Small, and Ted Wyder. Much of the work on the residual star formation has been performed by Sugata Kaviraj, Sadegh Khochfar, Kevin Schawinski, Hyunjin Jeong, Yun-Kyeong Sheen, Dowon Yi, & Seok-Joo Joo. Works on the passive ellipticals have been led by Young-Wook Lee and Chang H. Ree. Lots of advice and criticism were presented by Alessandro Boselli, Jean-Michel Deharveng, Jose Donas, Mike Rich, and Samir Salim. GALEX is a NASA’s small explorer mission funded by NASA. This work was supported by grant No. R01-2006-000-10716-0 from the Basic Research Program of the KOSEF.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science