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arXiv · 0711.2958

X-ray supernova remnants in nearby galaxies

Abstract

We present the initial results from a study of the SNR population in a sample of six nearby galaxies (NGC 2403, NGC 4214, NGC 4449, NGC 5204, NGC 3077, NGC 4395) based on Chandra archival data. We discuss the analysis of the Chandra data and we present candidate SNR sources selected on the basis of their X-ray colours. We also present deep [S II] 6716 & 6731 A and Halpha line images for most of the galaxies in our sample, which provide optically selected samples of SNRs. Comparison of the X-ray results with the complementary optical observations provides a more complete picture of the SNR population and allows us to address their X-ray emission. Our preliminary analysis of the [S II]/Halpha images show that 48 X-ray sources are typically associated with Halpha sources, 7 of which are SNR candidates based on their [S II]/Halpha ratio and one is an already known radio SNR.

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Ioanna Leonidaki, Andreas Zezas, Panayotis Boumis. 2007-11-19. X-ray supernova remnants in nearby galaxies. https://arxiv.org/abs/0711.2958

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