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arXiv · 2102.12497

Dissecting the inner Galaxy with $γ$-ray pixel count statistics

Francesca Calore·Fiorenza Donato·Silvia Manconi
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Abstract

We combine adaptive template fitting and pixel count statistics in order to assess the nature of the Galactic center excess in Fermi-LAT data. We reconstruct the flux distribution of point sources well below the Fermi-LAT detection threshold, and measure their radial and longitudinal profiles in the inner Galaxy. We find that all point sources $and$ the bulge-correlated diffuse emission each contributes $\mathcal{O}$(10\%) of the total inner Galaxy emission, and disclose a potential sub-threshold point-source contribution to the Galactic center excess.

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Francesca Calore, Fiorenza Donato, Silvia Manconi. 2021-10-28. Dissecting the inner Galaxy with $γ$-ray pixel count statistics. https://doi.org/10.1103/physrevlett.127.161102

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