NPAC (Nuclear/Particle/Astro/Cosmo) Forums |
Organized by: Prof. Lu Lu
Events on Thursday, November 11th, 2010
- Discovery of gamma-ray Emission from Andromeda Galaxy
- Time: 4:00 pm
- Place: 4274 Chamberlin
- Speaker: Hakki Ogelman, University of Wisconsin at Madison
- Abstract: 2 years worth of archival FERMI-LAT data was used to search forgamma-ray
emission from the Andromeda galaxy; the data show no noticeabla gamma-ray image.On-off source aperture photometry using a CO image template shows a 7 sigma excess in the on-source apertures in comparison to the off-source apertures. yielding a flux of (4.95 +/- 0.71`)x10^(-8) photonscm^-2 s^-1 at energies E>100 MeV. The likely origin of this flux will be discussed in terms of the cosmic-ray content and the interstellar gas at Andromeda. - Host: Daniel Chung