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arXiv · 1207.5975

The Type IIb Supernova 2011dh from a Supergiant Progenitor

Melina C. Bersten·Omar G. Benvenuto·Ken'ichi Nomoto·Mattias Ergon·Gastón Folatelli·Jesper Sollerman·Stefano Benetti·Maria Teresa Botticella·Morgan Fraser·Rubina Kotak·Keiichi Maeda·Paolo Ochner·Lina Tomasella
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Abstract

A set of hydrodynamical models based on stellar evolutionary progenitors is used to study the nature of SN 2011dh. Our modeling suggests that a large progenitor star ---with R ~200 Rsun---, is needed to reproduce the early light curve of SN 2011dh. This is consistent with the suggestion that the yellow super-giant star detected at the location of the SN in deep pre-explosion images is the progenitor star. From the main peak of the bolometric light curve and expansion velocities we constrain the mass of the ejecta to be ~2 Msun, the explosion energy to be E= 6-10 x 10^50 erg, and the 56Ni mass to be approximately 0.06 Msun. The progenitor star was composed of a helium core of 3 to 4 Msun and a thin hydrogen-rich envelope of ~0.1 M_sun with a main sequence mass estimated to be in the range of 12--15 Msun. Our models rule out progenitors with helium-core masses larger than 8 Msun, which correspond to M_ZAMS > 25 Msun. This suggests that a single star evolutionary scenario for SN 2011dh is unlikely.

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Melina C. Bersten, Omar G. Benvenuto, Ken'ichi Nomoto, Mattias Ergon, Gastón Folatelli, Jesper Sollerman, Stefano Benetti, Maria Teresa Botticella, Morgan Fraser, Rubina Kotak, Keiichi Maeda, Paolo Ochner, Lina Tomasella. 2012-07-25. The Type IIb Supernova 2011dh from a Supergiant Progenitor. https://doi.org/10.1088/0004-637x/757/1/31

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