Supernova remants in the Large Magellanic Cloud.

Abstract

view Abstract Citations (215) References (22) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Supernova remnants in the Large Magellanic Cloud. Mathewson, D. S. ; Clarke, J. N. Abstract Nine supernova remnants (SNRs) have been discovered in the Large Magellanic Cloud (LMC) using a combination of radio and optical techniques. The Mills Cross of the Molonglo Radio Observatory operating at 408 MHz was used to obtain the radio-source data, and a technique involving narrow-band image tube photography with the 102-cm reflector at Siding Spring Observatory was used to distinguish SNRs from H ii regions. All of the SNR are in extreme Population I regions. The relation between surface brightness and linear diameter D for the SNRs in the LMC is cc D -3, very similar to that of galactic SNRs although the mean surface brightness of an SNR in the LMC is about 70 percent greater than that of a galactic SNR with the same diameter. This may be explained either if the mean initial energy of a SNR in the LMC is 25 percent greater than that of a galactic SNR or if the distance to the LMC is 46 kpc and not 55 kpc. If equipartition is assumed between magnetic and particle energies, then the magnetic field strength B cc D -`, which is the relation for an expanding shell of constant thickness. An evolutionary trend was discovered in the Ha + [N ii] surface brightness, A such that I cc D - . An integral luminosity function of the type n(< D) = 1.8 x 10- is suggested from which a frequency of SNRs in the LMC of 1 in 500 years is deduced, in agreement with the predictions of Tammann. Two very extended nonthermal radio sources were discovered with linear sizes of approximately 250 pc. They are tentatively identified as sections of the giant shells of 2 super-supernovae which Westerlund and Mathewson suggested to have occurred in the regions of Constellations II and III. Subject headings: Magellanic Clouds - nebulae - radio sources - supernova remnants Publication: The Astrophysical Journal Pub Date: March 1973 DOI: 10.1086/152002 Bibcode: 1973ApJ...180..725M full text sources ADS | data products SIMBAD (19)