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.… 展开作者
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
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.
Integral field spectroscopy of supernova explosion sites: constraining mass and metallicity of the progenitors -- II. Type II-P and II-L supernovae
利用积分场光谱学已经观测到了附近星系中II-P和II-L型超新星的13个爆炸点，使得对爆炸点的空间和光谱研究成为可能。我们利用同时代超新星祖先星的母恒星星族的性质来推导它的金属丰度和初始质量（c.f. Paper I）。母恒星星族的光谱通过强线方法得到金属丰度的估计，并通过与简单的恒星星族（SSP）模型的比较得到年龄。这些金属丰度和年龄参数被采用的祖星。通过与恒星演化模型的比较，利用恒星的年龄或寿命来推导恒星的初始质量。利用这种技术，我们能够确定我们样品中SN祖细胞的金属丰度和初始质量。我们的结果表明，一些II型超新星的祖先可能是质量与SN Ib/c祖先相当的恒星。
