Five Mature Supernova Remnants in the Large Magellanic Cloud

John R. Dickel, D. K. Milne
1998 Astronomical Journal  
Radio observations of the extended supernova remnants (SNRs) N23 : SNR, N120 : SNR, 0525[660, N49, and N44 : shell 3 in the Large Magellanic Cloud show a variety of structures and little di †erence from shell SNRs in the Milky Way. N23 : SNR and N120 : SNR have very regular outlines, but the shells are much brighter on the sides toward the most prominent parts of their associated H II region complexes, probably reÑecting density gradients in the surroundings. N23 : SNR has a mixed magnetic Ðeld
more » ... mixed magnetic Ðeld orientation and a mean magnetic Ðeld strength of 15 kG. Its magnetic energy is about 4 times less than the relativistic electron energy. SNR 0525[660 appears to be isolated in the northern region of the LMC ; it has a partial shell of thin Ðlaments and some bright, patchy emission across the face of the remnant. N49, one of the brightest SNRs in the LMC, shows the strongest polarized emission in the west, where the total intensity is very weak, probably as a result of high magnetic Ðeld organization. N44 : shell 3, on the northeastern edge of a very large H II region complex, is deÐnitely conÐrmed as an SNR but has a di †erent central position and outline at radio wavelengths than it does at X-ray wavelengths.
doi:10.1086/300246 fatcat:wcvbjpue7zenzhl5vmxpwp5jia