2013/01/07 by H. E. S. S. Collaboration, :, A. Abramowski +211 · 1 citation
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #astro-ph.HE
paper · pdf · doi:10.1103/physrevlett.110.041301
published as Phys. Rev. Lett. 110, 041301 (2013) · 6 pages, 4 figures, accepted for publication in Phys. Rev. Lett
arxiv created 2013/01/07 · openalex publication_date 2013/01/22 · arxiv updated 2013/01/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
Gamma-ray line signatures can be expected in the very-high-energy (E_\ensuremathγ>100 GeV) domain due to self-annihilation or decay of dark matter (DM) particles in space. Such a signal would be readily distinguishable from astrophysical \ensuremathγ-ray sources that in most cases produce continuous spectra that span over several orders of magnitude in energy. Using data collected with the H.E.S.S. \ensuremathγ-ray instrument, upper limits on linelike emission are obtained in the energy range between \ensuremath∼500 GeV and \ensuremath∼25 TeV for the central part of the Milky Way halo and for extragalactic observations, complementing recent limits obtained with the Fermi-LAT instrument at lower energies. No statistically significant signal could be found. For monochromatic \ensuremathγ-ray line emission, flux limits of (2\ifmmode×\else\texttimes\fi10^\ensuremath-7--2\ifmmode×\else\texttimes\fi10^\ensuremath-5) m^\ensuremath-2 s^\ensuremath-1 sr^\ensuremath-1 and (1\ifmmode×\else\texttimes\fi10^\ensuremath-8--2\ifmmode×\else\texttimes\fi10^\ensuremath-6) m^\ensuremath-2 s^\ensuremath-1 sr^\ensuremath-1 are obtained for the central part of the Milky Way halo and extragalactic observations, respectively. For a DM particle mass of 1 TeV, limits on the velocity-averaged DM annihilation cross section ⟨\ensuremathσv⟩_\ensuremathχ\ensuremathχ\ensuremath→\ensuremathγ\ensuremathγ reach \ensuremath∼10^\ensuremath-27 cm3 s^\ensuremath-1, based on the Einasto parametrization of the Galactic DM halo density profile.