Dark matter gamma-ray line searches toward the Galactic Center halo with H.E.S.S. I

Lucia Rinchiuso; Emmanuel Moulin; Aion Viana; Christopher Van Eldik; Johannes Veh

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arXiv · 1708.08358

Dark matter gamma-ray line searches toward the Galactic Center halo with H.E.S.S. I

Lucia Rinchiuso·Emmanuel Moulin·Aion Viana·Christopher Van Eldik·Johannes Veh

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Abstract

The presence of dark matter is nowadays widely supported by a large body of astronomical and cosmological observations. A large amount of dark matter is expected to be present in the central region of the Milky Way. Very-high-energy (>100 GeV) {\gamma}-rays can be produced in the annihilation of dark matter particles. The H.E.S.S. array of Imaging Atmospheric Cherenkov Telescopes is a powerful tools to observe the Galactic Centre trying to detect {\gamma}-rays from dark matter annihilation. A new search for a dark matter signal has been carried out on the full H.E.S.S.-I data set of 2004-2014 observations. A 2D-binned likelihood method has been applied to exploit the spectral and spatial properties of signal and background. Updated constraints are derived on the velocity-weighted annihilation cross section for signals from prompt annihilation of dark matter particles into two photons. The larger statistics from the 10-year Galactic Center dataset of H.E.S.S.-I together with the 2D-analysis technique allows to significantly improve the previous limits.

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Lucia Rinchiuso, Emmanuel Moulin, Aion Viana, Christopher Van Eldik, Johannes Veh. 2017-08-28. Dark matter gamma-ray line searches toward the Galactic Center halo with H.E.S.S. I. https://arxiv.org/abs/1708.08358

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