About Us
MSU-UM High Energy Interchange Talk Program
The Michigan State University - University of Michigan High Energy Interchange Talk Program is held on select Fridays. The talks switch between Michigan State and the University of Michigan. Lectures held at UofM are held at noon in the owl room (845 Dennison building).
Maps and directions to the department.
For more information contact Renato Dupke.
Members of the UM Department of Astronomy who wish tp schedule time to meet with the speaker from MSU should contact Jimmy Irwin.
| Current And Upcoming Events | ||
| Date, Time and Location | Speaker | Abstract |
| Mon, Apr 21 2008 2:00 pm 1400 BPS | Monica Valluri U of M Astronomy | Evolution of phase space density in dark matter halos It has been known for many years that the phase space density profiles of dark matter particles obtained from cosmological N-body simulations are described by power-law profiles. I will present results of an analysis of the evolution of phase space density in DM halos and show how these power-law profiles arise naturally in hierarchical clustering scenarios. I will briefly discuss the implications of these results for our understanding of the properties of dark matter particles. |
| Recent talks | ||
| Date, Time and Location | Speaker | Abstract |
| Fri, Jun 15 2007 12:00 pm Owl | Dr. Arunav Kundu MSU dept of Physics and Astronomy | Implications of the Low Mass X-Ray Binaries - Globular Cluster Link Low mass X-ray binaries (LMXBs) are among the most visible tracers of neutron stars and black holes. The Chandra and XMM telescopes have discovered large populations of LMXBs in nearby galaxies. Recent studies have showed remarkably, that half the LMXBs in these galaxies are associated with globular clusters. The specific characteristics of individual globular clusters, such as metallicity and age, and the wide range of globular cluster properties in these galaxies provide a unique window into the formation and evolutionary histories of LMXBs. I present results from our recent studies of the LMXB-globular cluster connection in nearby galaxies, including the discovery of a black hole X-ray binary in a globular cluster, and discuss the implications on LMXB, globular cluster, and galaxy formation and evolution. |
| Fri, Jul 13 2007 2:00 pm 1400 BPS | Joel Bregman U of M Astronomy | The Missing Hot Baryons in the Local Universe |
| Fri, Aug 17 2007 12:00 pm Owl | Ming Sun MSU dept of Physics and Astronomy | X-ray gas of galaxies in clusters: mini-cooling cores, AGN feedback, stripping and star formation I will discuss the population properties of X-ray thermal coronae of early-type galaxies in nearby hot clusters. Cool galactic coronae (kT= 0.5-1.1 keV) have been found to be common, > 60% in > 2 L* galaxies. Their survival from ICM stripping, evaporation, rapid cooling, and powerful AGN outflows provide rich information on gas stripping, microscopic transport and feedback processes in the cluster environment. Updates based on new Chandra data will also be presented. Late-type galaxies evolve significantly in clusters. I will discuss one example with rich phenomena in X-rays and Halpha, the starburst galaxy ESO 137-001 in the nearby massive cluster A3627. A 70 kpc narrow X-ray tail and a 40 kpc Halpha tail have been found, as well as at least 29 HII regions downstream of the galaxy. The high surface number density and luminosities of these HII regions dwarf the previously known examples of isolated HII regions in clusters. We suggest that stripping of the ISM not only contributes to the ICM, but also adds to the intracluster stellar light through subsequent star formation. |
| Thu, Sep 20 2007 1:30 pm 1400 BPS | Jimmy Irwin U of M Astronomy | The Low Metallicity ISM of X-ray Faint Elliptical Galaxies Since the hot interstellar medium (ISM) of early-type galaxies is believed to originate primarily from stellar mass loss and supernovae, the metallicity of the ISM should reflect that of the stars contributing the mass to the ISM. This has been confirmed for gas-rich X-ray bright ellipticals, as both the X-ray-determined ISM abundances and optically-determined stellar abundances are approximately solar. However, this does not seem to be the case for gas-poor, X-ray faint ellipticals, for which very sub-solar abundances have been reported, although poor statistics and significant X-ray binary contamination have been listed as the cause of these (erroneously) low abundance measurements. We present Chandra + XMM-Newton spectra of one of the best-observed X-ray faint ellipticals, NGC4697, and confirm that O, Ne, Mg, Si, Fe, and Ni are all significantly subsolar, and are not the result of poor spectral fitting or poor statistics. We speculate that the low metal abundances are the result of dilution from the accretion over time of pristine metal-free gas that surrounds the galaxy. |
| Fri, Oct 19 2007 12:00 pm Owl | Mark Voit MSU dept of Physics and Astronomy | |
| Fri, Nov 30 2007 12:00 pm 1400 BPS | Brian Nord, Rebecca Stanek and Elena Rasia U of M Astronomy | Brian Nord TITLE: Effects of Selection and Covariance on Scaling Relations of X-ray Galaxy Clusters Rebecca Stanek: TITLE:The Effect of Baryonic Physics on the Halo Mass Function Elena Rasia TITLE: Testing scaling relation and their scatter with a bullet-like simulated cluster |
| Fri, Mar 14 2008 12:00 pm Owl | Stephen, I Chun Shih MSU dept of Physics and Astronomy | The globular cluster black hole in NGC 4472 Maccarone et al. (2007) discovered the existence of an X-ray emitting black hole in a globular cluster in NGC 4472. This source is soft and luminous, alone with rapid variability in count rate by a factor of 7. In this talk, I'll discuss the nature of the source and the cause of the variability, which is most likely due to a partial obscuration by a precessing warped accretion disk. |
