Data Centre for Astrophysics
Astronomy Department of the University of Geneva
ISDC Seminar

Thursday, 9th April 2020 at 14:00

Celine Armand
Lapp theorique LAPP Annecy

Dark matter searches with γ-ray data. use to connect

Abstract. In the indirect dark matter (DM) detection framework, DM particles would produce some signals by self-annihilating and creating standard model products such as γ rays, which may be detected by ground- and space-based telescopes. Dwarf galaxies represent promising targets for the DM search as they are believed to be DM dominated and possess a reduced astrophysical background. The H.E.S.S. telescopes observed three different kinds of these objects known as dwarf irregular, dwarf spheroidal, and dwarf ultrafaint galaxies. We search for a DM signal looking for excess of γ rays towards these dwarf galaxies. We present the results on these observations interpreted in terms of velocity-weighted cross section for DM self-annihilation hσvi as a function of DM particle mχ mass for several annihilation channels. Another source we study is the nearest galaxy, Andromeda galaxy (M31). This source contains a non negligible astrophysical component that we need to characterize before studying a potential DM signal. We present the ongoing work on M31 morphology using the γ-ray data of Fermi-LAT. The results are obtained with skyFACT, a new method of γ-ray fitting which combines template fitting and image reconstruction.