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Register a new userDiscovery of gamma-ray emission from the supernova remnant Kes 17 with Fermi Large Area Telescope
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Added by
Chung Yue Hui David
Publication date
2011
fields
Physics
and research's language is
English
Authors
J. H. K. Wu
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We report the discovery of GeV emission at the position of supernova remnant Kes 17 by using the data from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. Kes 17 can be clearly detected with a significance of ~12 sigma in the 1 - 20 GeV range. Moreover, a number of gamma-ray sources were detected in its vicinity. The gamma-ray spectrum of Kes 17 can be well described by a simple power-law with a photon index of ~ 2.4. Together with the multi-wavelength evidence for its interactions with the nearby molecular cloud, the gamma-ray detection suggests that Kes 17 is a candidate acceleration site for cosmic-rays.
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The remnant of supernova explosion is widely believed to be the acceleration site of high-energy cosmic ray particles. The acceleration timescale is, however, typically very long. Here we report the detection of a variable $gamma$-ray source with the Fermi Large Area Telescope, which is positionally and temporally consistent with a peculiar supernova, iPTF14hls. A quasi-stellar object SDSS J092054.04+504251.5, which is probably a blazar according to the infrared data, is found in the error circle of the $gamma$-ray source. More data about the $gamma$-ray source and SDSS J092054.04+504251.5 are needed to confirm their association. On the other hand, if the association between the $gamma$-ray source and the supernova is confirmed, this would be the first time to detect high-energy $gamma$-ray emission from a supernova, suggesting very fast particle acceleration by supernova explosions.
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