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Detection of Sub-TeV Gamma-Rays from the Galactic Center Direction by CANGAROO-II

K. Tsuchiya·R. Enomoto·L. T. Ksenofontov·M. Mori·T. Naito·CANGAROO-II collaboration
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Abstract

We have detected sub-TeV gamma-ray emission from the direction of the Galactic Center (GC) using the CANGAROO-II Imaging Atmospheric Cherenkov Telescope (IACT). We detected a statistically signicant excess at energies greater than 250GeV. The flux was one order of magnitude lower than that of Crab at 1 TeV with a soft spectrum E^{-4.6+-0.5}. The signal centroid is consistent with the GC direction and the observed prole is consistent with a point-like source. Our data suggests that the GeV source 3EG J1746-2851 is identical with this TeV source and we study the combined spectra to determine the possible origin of the gamma-ray emission. We also obtain an upper limit on the cold dark-matter density in the Galactic halo.

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K. Tsuchiya, R. Enomoto, L. T. Ksenofontov, M. Mori, T. Naito, CANGAROO-II collaboration. 2004-03-25. Detection of Sub-TeV Gamma-Rays from the Galactic Center Direction by CANGAROO-II. https://doi.org/10.1086/421292

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