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Chemical enrichment of the complex hot ISM of the Antennae galaxies: I. Spatial and spectral analysis of the diffuse X-ray emission

A. Baldi·J. C. Raymond·G. Fabbiano·A. Zezas·A. H. Rots·F. Schweizer·A. R. King·T. J. Ponman
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Abstract

We present an analysis of the properties of the hot interstellar medium (ISM) in the merging pair of galaxies known as The Antennae (NGC 4038/39), performed using the deep, coadded ~411 ks Chandra ACIS-S data set. These deep X-ray observations and Chandra's high angular resolution allow us to investigate the properties of the hot ISM with unprecedented spatial and spectral resolution. Through a spatially resolved spectral analysis, we find a variety of temperatures (from 0.2 to 0.7 keV) and Nh (from Galactic to 2x10^21 cm^-2). Metal abundances for Ne, Mg, Si, and Fe vary dramatically throughout the ISM from sub-solar values (~0.2) up to several times solar.

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A. Baldi, J. C. Raymond, G. Fabbiano, A. Zezas, A. H. Rots, F. Schweizer, A. R. King, T. J. Ponman. 2005-09-01. Chemical enrichment of the complex hot ISM of the Antennae galaxies: I. Spatial and spectral analysis of the diffuse X-ray emission. https://doi.org/10.1086/497914

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