EXPLORING THE DARK ACCELERATOR HESS J1745-303 WITH THE FERMI LARGE AREA TELESCOPE

Journal Article · Sun Jul 10 00:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/735/2/115· OSTI ID:21578386

Hui, C Y ^[1]; Wu, E M. H.; Wu, J H. K.; Cheng, K S ^[2]; Huang, R H. H.; Tam, P H. T.; Kong, A K. H. ^[3]

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1. Department of Astronomy and Space Science, Chungnam National University, Daejeon 305-764 (Korea, Republic of)
2. Department of Physics, University of Hong Kong, Pokfulam Road (Hong Kong)
3. Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu, Taiwan (China)

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 its first {approx}29 month observation. The source can clearly be detected at the levels of {approx}18{sigma} and {approx}6{sigma} 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 {Gamma} {approx} 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'.

• OSTI ID: 21578386
• Journal Information: Astrophysical Journal, Vol. 735, Issue 2; Other Information: DOI: 10.1088/0004-637X/735/2/115; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ACCELERATORS
COSMIC GAMMA SOURCES
EMISSION
SPECTRA
COSMIC RAY SOURCES