Note: Event at 2 PM

Speaker: Matthew Reece, Harvard University

When: September 7, 2012 (Fri), 02:00PM to 03:00PM (add to my calendar)

Location: PRB 595

Recent analyses of Fermi-LAT gamma ray data (by Weniger, Su, and Finkbeiner) have found some evidence for monoenergetic features ("lines") in the data at about 111 and 129 GeV, from photons near the galactic center and, with less significance, from other points in the sky not known to correspond to astronomical objects. I will describe what has been found and discuss some of the particle physics possibilities if the lines are interpreted as arising from dark matter annihilation. In particular, I will point out the possibility that the lines are associated with a hidden sector that couples to the Standard Model only at the nonrenormalizable level, and explore bounds on the scale suppressing these couplings. I will also discuss constraints on the case that the new physics is more strongly coupled, and in particular the extent to which new charged particles could simultaneously explain the gamma ray lines and modifications to Higgs decay widths.