ABSTRACT The LMC supernova remnant N 63 A is located near the center of the small association NGC 2030. Observations of the most luminous association member, combined with evolutionary models incorporating conservative mass-loss rates, yield a mass of 30 solar masses for the brightest star in NGC 2030. Since association members are approximately coeval the supernova precursor must have had a mass not less than 30 solar masses. Both the optical morphology and the radio spectral index of N 63 A show that it is not a plerionic SNR. This provides a counter example to the suggestion that massive O-type stars are the progenitors of Crab-like remnants.
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