2011/04/26 by C. Y. Hui, E. M. H. Wu, J. H. K. Wu +4
Earth and Planetary Sciences · Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Compton scattering #Earth Systems and Cosmic Evolution #Fermi Gamma-ray Space Telescope #Particle acceleration #Photon #Spectral index #Spectral line #Spitzer Space Telescope #Telescope #astro-ph.HE
paper · pdf · doi:10.1088/0004-637x/735/2/115
8 pages, 3 figures, 1 table, accepted for publication in ApJ
arxiv created 2011/04/26 · openalex publication_date 2011/06/23 · arxiv updated 2015/05/28 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We present a detailed analysis of the γ-ray emission from HESS J1745-303 with the data obtained by the Fermi Gamma-ray Space Telescope in its first ∼29 month observation. The source can clearly be detected at the levels of ∼18σ and ∼6σ in 1–20 GeV and 10–20 GeV, respectively. We do not find any evidence of the variability seen in the results obtained by the Compton Gamma-ray Observatory . Most of the emission in 10–20 GeV is found to coincide with region C of HESS J1745-303. A simple power law is sufficient to describe the GeV spectrum with a photon index of Γ ∼ 2.6. The power-law spectrum inferred in the GeV regime can be connected to that of a particular spatial component of HESS J1745-303 in 1–10 TeV without any spectral break. These properties impose independent constraints for understanding the nature of this "dark particle accelerator."