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The Discovery of a Spatially-Resolved Supernova Remnant in M31 with Chandra

A. K. H. Kong·M. R. Garcia·F. A. Primini·S. S. Murray
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Abstract

Chandra observations of M31 allow the first spatially resolved X-ray image of a supernova remnant (SNR) in an external spiral galaxy. CXOM31 J004327.7+411829 is a slightly elongated ring-shaped object with a diameter of ~11'' (42 pc). In addition, the X-ray image hints that the chemical composition of the SNR is spatial dependent. The X-ray spectrum of the SNR can be well fitted with a Raymond-Smith model or a non-equilibrium ionization model. Depending on the spectral model, the 0.3-7 keV luminosity is between 3.2x10^36 erg/s and 4.5x10^37 erg/s. The age of the SNR is estimated to be 3210-22300 years and the number density of ambient gas is ~0.003-0.3 cm^-3. This suggests that the local interstellar medium around the SNR is low.

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A. K. H. Kong, M. R. Garcia, F. A. Primini, S. S. Murray. 2002-10-17. The Discovery of a Spatially-Resolved Supernova Remnant in M31 with Chandra. https://doi.org/10.1086/345610

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