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X-ray luminous star-forming galaxies

A. L. Zezas·I. Georgantopoulos·M. J. Ward
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Abstract

We present results from the cross-correlation of the spectroscopic atlas of Ho etal (1995) with the ROSAT All-Sky Survey Bright Source Catalogue, in an attempt to understand the X-ray emission mechanisms in nearby galaxies. The resulting sample of 45 galaxies consists predominantly of AGN. However, there are several starforming galaxies spanning a wide range of X-ray luminosities (~10^{38} - 10^{42} erg s^{-1}). We have analyzed ROSAT and ASCA data for the two most luminous star-forming galaxies, namely NGC3310 and NGC3690. We find that their 0.1-10 keV X-ray spectra can be fitted by a soft thermal plasma of kT$\sim0.8$ keV and a harder component with kT~10-15 keV or a power-law with Gamma~1.6. These are very similar to the spectra of the archetypal star-forming galaxies NGC253 and M82.

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A. L. Zezas, I. Georgantopoulos, M. J. Ward. 1999-06-24. X-ray luminous star-forming galaxies. https://doi.org/10.1080/10556799908202998

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