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arXiv · 1104.4836

Exploring the dark accelerator HESS J1745-303 with Fermi Large Area Telescope

C. Y. Hui·E. M. H. Wu·J. H. K. Wu·R. H. H. Huang·K. S. Cheng·P. H. T. Tam·A. K. H. Kong
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Abstract

We present a detailed analysis of the gamma-ray emission from HESS J1745-303 with the data obtained by the Fermi Gamma-ray Space Telescope in the first ~29 months observation.The source can be clearly detected at the level of ~18-sigma and ~6-sigma in 1-20 GeV and 10-20 GeV respectively. Different from the results obtained by the Compton Gamma-ray Observatory, we do not find any evidence of variability. Most of emission in 10-20 GeV is found to coincide with the region C of HESS J1745-303. A simple power-law is sufficient to describe the GeV spectrum with a photon index of ~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".

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C. Y. Hui, E. M. H. Wu, J. H. K. Wu, R. H. H. Huang, K. S. Cheng, P. H. T. Tam, A. K. H. Kong. 2011-04-26. Exploring the dark accelerator HESS J1745-303 with Fermi Large Area Telescope. https://doi.org/10.1088/0004-637x/735/2/115

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