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Chandra Observations of "The Antennae" Galaxies (NGC 4038/39): II. Detection and Analysis of Galaxian X-ray source

A. Zezas·G. Fabbiano·A. H. Rots·S. S. Murray
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Abstract

We report the detailed analysis of the X-ray properties of the discrete sources detected in a long (72 ks) \chandra ACIS-S observation of the Antennae galaxies. We detect 49 sources, down to a detection limit of ~ 10^{38} erg\s; 18 sources have Lx >10^{39} erg\s (Ultra Luminous X-ray sources; ULXs). Six of the 49 sources have an extended component. Two sources show evidence for variability during this observation, and three sources exhibit long term variability in timescales of a few years. The spectra of the discrete sources are diverse, suggesting different emission mechanisms, broadly correlated with the source luminosity: the most luminous sources exhibit harder emission, while the spectra of fainter sources appear softer. Spectra and variability suggest that the ULXs may be binary accretion sources; Supernova remnants or hot ISM in the Chandra beam may be responsible for some of the softer sources.

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A. Zezas, G. Fabbiano, A. H. Rots, S. S. Murray. 2002-03-12. Chandra Observations of "The Antennae" Galaxies (NGC 4038/39): II. Detection and Analysis of Galaxian X-ray source. https://doi.org/10.1086/342010

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