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An ASCA Study of the W51 Complex

Bon-Chul Koo·Jae-Joon Lee·Frederick D. Seward
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Abstract

We present the analysis of ASCA archival data from the Galactic source W51. The ASCA spectra show that the soft (kT<= 2.5 keV) X-rays are of thermal origin and are compatible with W51C being a single, isothermal (kT~0.3 keV) supernova remnant at the far-side of the Sagittarius arm. The ASCA images reveal hard (kT>=2.5 keV) X-ray sources which were not seen in previous X-ray observations. Some of these sources are coincident with massive star-forming regions and the spectra are used to derive X-ray parameters. By comparing the X-ray absorbing column density with atomic hydrogen column density, we infer the location of star-forming regions relative to molecular clouds. There are unidentified hard X-ray sources superposed on the supernova remnant and we discuss the possibility of their association.

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Bon-Chul Koo, Jae-Joon Lee, Frederick D. Seward. 2001-12-15. An ASCA Study of the W51 Complex. https://doi.org/10.1086/339179

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