22-29 July 2015
Europe/Vienna timezone

Dark matter signals from the gamma-ray sky

Jul 24, 2015, 11:30 AM
15m
HS33

HS33

talk Astroparticle Physics, Cosmology, Gravitation Astroparticle Physics, Cosmology, Gravitation

Speaker

Francesca Calore (University of Amsterdam)

Description

Unveiling the nature of dark matter is one of the biggest challenges of particle physics and cosmology. Beside direct detection and collider experiments, it is possible to look for a dark matter signal through indirect searches whose goal is to disentangle the signal from particle dark matter annihilation or decay from the large astrophysical background. I will discuss messengers and targets for indirect dark matter searches and I will then focus on gamma rays, the golden channel for dark matter indirect searches. Since its launch in 2008, the Fermi-LAT is taking snap-shots of the whole gamma-ray sky with unprecedented accuracy. Besides astrophysical processes, the gamma rays collected by the Fermi-LAT offer the unique possibility to probe dark matter at the center of the Milky Way. Recently, a spatially extended excess of gamma rays collected by the Fermi-LAT from the inner region of the Milky Way has been claimed by different and independent groups. I will review previous analyses claiming the discovery of a spatially extended excess of gamma rays above standard astrophysical backgrounds. I will then characterise the spatial and spectral properties of such an extended diffuse emission in light of background model systematics. Finally, I will scrutinise the most promising interpretations - among others, the possibility that the signal originates from dark matter annihilation - in order to shed light onto the origin of this yet unknown extra-emission at the Galactic Center.

Primary author

Francesca Calore (University of Amsterdam)

Presentation materials