Events on Thursday, January 31st, 2008
- R. G. Herb Condensed Matter Seminar
- Physics at the University of Nebraska-Lincoln
- Time: 10:00 am
- Place: 5310 Chamberlin Hall
- Speaker: Evgeny Tsymbal, Physics, University of Nebraska-Lincoln
- Host: Rzchowski
- Astronomy Colloquium
- Not Your Grandmother's HII Regions: An X-ray Tour of Massive Star- forming Regions
- Time: 12:00 pm
- Place: 6515 Sterling Hall (coffee at 11:30 am in 6521 Sterling)
- Speaker: Leisa Townsley, Penn State
- Abstract: The Chandra X-ray Observatory is providing remarkable new views of massive star-forming regions, revealing all stages in the life cycle of high-mass stars and their effects on their surroundings. We will tour several such regions, highlighting physical processes that characterize the life of a cluster of massive stars, from deeply- embedded cores too young to have established an HII region to superbubbles so large that they shape our views of galaxies. Along the way we see that X-ray observations reveal hundreds of pre-main sequence stars accompanying the massive stars that power great HII region complexes. The most massive stars themselves are often anomalously hard X-ray emitters; this may be a new indicator of close binarity or strong magnetic fields. These complexes are sometimes suffused by diffuse X-ray structures, signatures of multi-million- degree plasmas created by fast O-star winds. In older regions we see the X-ray remains of the deaths of massive stars that stayed close to their birthplaces, exploding as cavity supernovae within the superbubbles that these clusters created.