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arXiv · astro-ph/0410688

Hard X-ray Emission Clumps in the gamma-Cygni Supernova Remnant: an INTEGRAL-ISGRI View

A. M. Bykov·A. M. Krassilchtchikov·Yu. A. Uvarov·H. Bloemen·R. A. Chevalier·M. Yu. Gustov·W. Hermsen·F. Lebrun·T. A. Lozinskaya·G. Rauw·T. V. Smirnova·S. J. Sturner·J. -P. Swings·R. Terrier·I. N. Toptygin
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Abstract

Spatially resolved images of the galactic supernova remnant G78.2+2.1 (gamma-Cygni) in hard X-ray energy bands from 25 keV to 120 keV are obtained with the IBIS-ISGRI imager aboard the International Gamma-Ray Astrophysics Laboratory INTEGRAL. The images are dominated by localized clumps of about ten arcmin in size. The flux of the most prominent North-Western (NW) clump is (1.7 +/- 0.4) 10^{-11} erg/cm^2/s in the 25-40 keV band. The observed X-ray fluxes are in agreement with extrapolations of soft X-ray imaging observations of gamma-Cygni by ASCA GIS and spatially unresolved RXTE PCA data. The positions of the hard X-ray clumps correlate with bright patches of optical line emission, possibly indicating the presence of radiative shock waves in a shocked cloud. The observed spatial structure and spectra are consistent with model predictions of hard X-ray emission from nonthermal electrons accelerated by a radiative shock in a supernova interacting with an interstellar cloud, but the powerful stellar wind of the O9V star HD 193322 is a plausible candidate for the NW source as well.

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A. M. Bykov, A. M. Krassilchtchikov, Yu. A. Uvarov, H. Bloemen, R. A. Chevalier, M. Yu. Gustov, W. Hermsen, F. Lebrun, T. A. Lozinskaya, G. Rauw, T. V. Smirnova, S. J. Sturner, J. -P. Swings, R. Terrier, I. N. Toptygin. 2004-10-28. Hard X-ray Emission Clumps in the gamma-Cygni Supernova Remnant: an INTEGRAL-ISGRI View. https://doi.org/10.1051/0004-6361%3A200400089

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