The Stellar Ancestry of Supernova Progenitors in the Magellanic Clouds - I. the Most Recent Supernovae in the Large Magellanic Cloud
Feb, 2009Citations per year
Abstract: (arXiv)
We use the star formation history map of the Large Magellanic Cloud recently published by Harris & Zaritsky to study the sites of the eight smallest (and presumably youngest) supernova remnants in the Cloud: SN 1987A, N158A, N49, and N63A (core collapse remnants), 0509-67.5, 0519-69.0, N103B, and DEM L71 (Type Ia remnants). The local star formation histories provide unique insights into the nature of the supernova progenitors, which we compare with the properties of the supernova explosions derived from the remnants themselves and from supernova light echoes. We find that core collapse supernovae are always associated with vigorous star formation in the recent past. In the case of SN 1987A, the time of the last peak of star formation (12 Myr) matches very well the lifetime of a star with the mass of its blue supergiant progenitor (20Msun). More recent peaks of star formation can lead to supernovae with more massive progenitors, which opens the possibility of a Type Ib/c origin for SNRs N158A and N63A. Stars more massive than 21.5Msun are very scarce around SNR N49, implying that the magnetar SGR 0526-66 in this SNR was either formed elsewhere or came from a progenitor with a mass well below the threshold suggested in the literature. Three of our four Ia SNRs are associated with old, metal poor stellar populations. This includes SNR 0509-67.5, which is known to have been originated by an extremely bright Type Ia event, and yet is located very far away from any sites of recent star formation, in a population with a mean age of 7.9 Gyr. The Type Ia SNR N103B, on the other hand is indeed associated with recent star formation, and might have had a relatively younger and more massive progenitor with substantial mass loss before the explosion.References(110)
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