2004/03/25 by K. Tsuchiya, R. Enomoto, L. T. Ksenofontov +50 · 1 citation
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Cosmic Phenomena #Crab Nebula #Dark Matter and Cosmic Phenomena #Dark matter #Flux (metallurgy) #Galactic Center #Galactic plane #Galaxy #Gamma ray #Halo #Physics #Radio Astronomy Observations and Technology #Spectral line #Telescope #astro-ph #hep-ex
paper · pdf · doi:10.1086/421292
published as Astrophys.J.606:L115-L118,2004 · 13 pages, 3 figures, aastex.cls, accepted by ApJ Letters
arxiv created 2004/03/25 · openalex publication_date 2004/04/09 · arxiv updated 2014/10/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We have detected sub-TeV gamma-ray emission from the direction of the Galactic center (GC) using the CANGAROO-II Imaging Atmospheric Cerenkov Telescope. We detected a statistically significant excess at energies greater than 250 GeV. The flux was 1 order of magnitude lower than that of the Crab Nebula at 1 TeV with a soft spectrum proportional to E -4.6±0.5 . The signal centroid is consistent with the GC direction, and the observed profile is consistent with a pointlike source. Our data suggest that the GeV source 3EG J1746-2851 is identical to 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.