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arXiv · astro-ph/0203190

A Mini-survey of X-ray Point Sources in Starburst and Non-Starburst Galaxies

Abstract

We present a comparison of X-ray point source luminosity functions of 3 starburst galaxies (the Antennae, M82, and NGC 253) and 4 non-starburst spiral galaxies (NGC 3184, NGC 1291, M83, and IC 5332). We find that the luminosity functions of the starbursts are flatter than those of the spiral galaxies; the starbursts have relatively more sources at high luminosities. This trend extends to early-type galaxies which have steeper luminosity functions than spirals. We show that the luminosity function slope is correlated with 60 micron luminosity, a measure of star formation. We suggest that the difference in luminosity functions is related to the age of the X-ray binary populations and present a simple model which highlights how the shape of the luminosity distribution is affected by the age of the underlying X-ray binary population.

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BibTeXRIS

R. E. Kilgard, P. Kaaret, M. I. Krauss, A. H. Prestwich, M. T. Raley, A. Zezas. 2002-03-12. A Mini-survey of X-ray Point Sources in Starburst and Non-Starburst Galaxies. https://doi.org/10.1086/340490

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