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Hard Extended X-ray Source in the IC 443 SNR Resolved by Chandra: A Fast Ejecta Fragment or a New Pulsar Wind Nebula?

A. M. Bykov·F. Bocchino·G. G. Pavlov
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Abstract

A Chandra observation of the isolated hard X-ray source XMMU J061804.3+222732, located in the region of apparent interaction of the supernova remnant IC 443 with a molecular cloud, resolved the complex structure of the source in a few bright clumps embedded in an extended emission of a ~ 30 arcsec size. The X-ray spectra of the clumps and the extended emission are dominated by a hard power-law component with a photon index of 1.2--1.4. In addition, we see some indications of an optically thin thermal plasma of a ~ 0.3 keV temperature. The observed X-ray morphology and spectra are consistent with those expected for an isolated supernova ejecta fragment interacting with a dense ambient medium. A possible alternative interpretation is a pulsar wind nebula associated with either IC 443 or another SNR, G189.6+3.3.

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A. M. Bykov, F. Bocchino, G. G. Pavlov. 2005-03-31. Hard Extended X-ray Source in the IC 443 SNR Resolved by Chandra: A Fast Ejecta Fragment or a New Pulsar Wind Nebula?. https://doi.org/10.1086/430499

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