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Two New X-ray/Optical/Radio Supernova Remnants in M31

B. F. Williams·L. O. Sjouwerman·A. K. H. Kong·J. D. Gelfand·M. R. Garcia·S. S. Murray
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Abstract

We compare a deep (37 ks) Chandra ACIS-S image of the M31 bulge to Local Group Survey narrow-band optical data and Very Large Array (VLA) radio data of the same region. Our precisely registered images reveal two new optical shells with X-ray counterparts. These shells have sizes, [S II]/H-alpha flux ratios, and X-ray spectral properties typical of supernova remnants (SNRs) with ages of 9$^{+3}_{-4}$ and 17$^{+6}_{-9}$ kyr. Analysis of complementary VLA data reveals the radio counterparts, further confirming that they are SNRs. We discuss and compare the properties and morphologies of these SNRs at the different wavelengths.

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B. F. Williams, L. O. Sjouwerman, A. K. H. Kong, J. D. Gelfand, M. R. Garcia, S. S. Murray. 2004-07-23. Two New X-ray/Optical/Radio Supernova Remnants in M31. https://doi.org/10.1086/424589

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