Search for Gamma-ray Spectral Lines with the Fermi Large Area Telescope and Dark Matter implications
by
Prof.Eric Charles(SLAC National Accelerator Laboratory)
→
Europe/Rome
131 (INFN edificio C)
131
INFN edificio C
Description
Weakly Interacting Massive Particles (WIMPs) are a theoretical class of particles that are excellent dark matter candidates. WIMP annihilation or decay may produce essentially monochromatic gamma rays detectable by the Fermi Large Area Telescope (LAT). Such interactions in the Milky Way would produce a narrow spectral line that could be observed against the astrophysical gamma-ray emission of the Galaxy. We have searched for spectral lines in the energy range 5--300 GeV using 3.7 years of data, reprocessed with updated instrument calibrations and an improved energy dispersion model compared to the one used in previous Fermi-LAT Collaboration line searches. We searched in five regions selected to optimize sensitivity to different theoretically-motivated density distributions of WIMPs. We present 95% confidence limits for WIMPs annihilation cross section and decay lifetimes. We extensively discuss potential systematic effects in the search. Finally, we consider claims of evidence for a spectral line at 130 GeV, compare our results to previous work, and discuss why this search finds a lower statistical significance for a potential line than other works.
