Ponente
Descripción
Our understanding of the $\gamma$-ray sky has improved dramatically in the past decade, however, the unresolved $\gamma$-ray background (UGRB) still has a potential wealth of information about the faintest $\gamma$-ray sources pervading the Universe. Statistical cross-correlations with tracers of cosmic structure can indirectly identify the populations that most characterize the $\gamma$-ray background. In this study, we analyze the angular correlation between the $\gamma$-ray background and the matter distribution in the Universe as traced by gravitational lensing and galaxy clustering analyses, leveraging more than a decade of observations from the $\textit{Fermi}$-Large Area Telescope (LAT) and 3 years of data from the Dark Energy Survey (DES). We provide results obtained so far from both the lensing and galaxy clustering analyses, and discuss the potential composition of the UGRB, and what it could imply for WIMP DM searches. We also comment on the astrophysical nature of the UGRB through phenomenological and physical modelling. Using a 2-halo model approach, we find that in both cases (i.e, lensing and galaxy clustering), the cross-correlations are stronger for the 2-halo component, implying a stronger presence of the large-scale structure in the signal compared to point-like objects.
