Oct 15 – 20, 2017
Congress Center Garmisch-Partenkirchen
Europe/Berlin timezone
The proceedings of the 7th Fermi Symposium are available at https://pos.sissa.it/312/

Study of the anisotropy of the unresolved gamma-ray background

Oct 19, 2017, 3:15 PM
GaPa/1-1 - Olympiasaal (Garmisch-Partenkirchen)

GaPa/1-1 - Olympiasaal


Contributed talk Extragalactic Diffuse & EBL Extragalactic diffuse & EBL II


Michela Negro


The Extragalactic gamma-ray Emission (EGB) is constituted by two essential parts: resolved gamma-ray sources, point-like or extended, and an isotropic component. Once the formers have been excluded (masked or subtracted), what remains is the latter component, called Unresolved Gamma-Ray Background (UGRB), which, at a deeper level, is not truly isotropic and includes contribution from unresolved populations of sources. Expanding the UGRB sky map into spherical harmonics gives a powerful mean to study the intensity fluctuations even at the smallest scales, which can give clues about what this component is made of.
In this analysis we study the UGRB anisotropy signal with 8 years of Fermi-LAT Pass 8 data. An energy-dependent mask has been built to cover each resolved source in addiction to a region around the Galactic plane. Preliminary results are compatible with at least two classes of point-like sources contributing the UGRB emission.

Primary author

Michela Negro

Presentation materials

Peer reviewing