Events at Physics |
Events on Tuesday, April 21st, 2009
- Chaos & Complex Systems Seminar
- Title to be announced
- Time: 12:05 pm
- Place: 4274 Chamberlin
- Speaker: Olga Trubetskoy, Pharmacy and Comparative Biosciences
- Astronomy Colloquium
- A Census of Baryons in Groups and Clusters of Galaxies
- Time: 3:30 pm - 5:00 pm
- Place: 6515 Sterling Hall
- Speaker: Ann Zabludoff, Univ of AZ, Steward Observatory
- Abstract: We have now discovered that intracluster stars are a significant part of the stellar baryons in galaxy clusters and groups. The detection of this previously unexplored baryonic component has consequences for the baryon budget of clusters and its relationship to the universal value obtained from WMAP observations of the cosmic microwave background radiation.
Because metals produced by intracluster stars do not need to escape from galaxies, but are instead directly injected into the intergalactic medium, the existence of this stellar population also has significant consequences for the enrichment history of the hot, X-ray-emitting, intracluster gas.
I will review our recent work characterizing the properties of
intracluster stars, as well as new constraints on missing baryons on the scales of clusters and groups, on whether it is possible to account for the high metal content of the intracluster medium, and on the mass profiles of the largest bound systems in the universe.
- Host: Professor Eric Wilcots