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arXiv · 0912.2071

On the progenitor and early evolution of the type II supernova 2009kr

M. Fraser·K. Takats·A. Pastorello·S. J. Smartt·S. Mattila·M-T. Botticella·S. Valenti·M. Ergon·J. Sollerman·S. Benetti·F. Bufano·R. M. Crockett·I. J. Danziger·J. R. Maund·S. Taubenberger·M. Turatto
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Abstract

We report the identification of a source coincident with SN 2009kr in HST pre-explosion images. The object appears to be a single point source with an intrinsic colour V-I = 1.1 and M_V = -7.6. If this is a single star it would be a yellow supergiant of log L/L_{sol} \sim 5.1 and a mass of 15 (+5/-4) M_{sol}. The spatial resolution does not allow us yet to definitively determine if the progenitor object is a single star, a binary system, or a compact cluster. We show that the early lightcurve is flat, similar to IIP SNe, but that the the spectra are somewhat peculiar, displaying unusual P-Cygni profiles. The evolution of the expanding ejecta will play an important role in understanding the progenitor object.

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M. Fraser, K. Takats, A. Pastorello, S. J. Smartt, S. Mattila, M-T. Botticella, S. Valenti, M. Ergon, J. Sollerman, S. Benetti, F. Bufano, R. M. Crockett, I. J. Danziger, J. R. Maund, S. Taubenberger, M. Turatto. 2009-12-10. On the progenitor and early evolution of the type II supernova 2009kr. https://doi.org/10.1088/2041-8205%2F714%2F2%2Fl280

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