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arXiv · 0709.1501

The Luminous and Carbon-Rich Supernova 2006gz: A Double Degenerate Merger?

M. Hicken·P. M. Garnavich·J. L. Prieto·S. Blondin·D. L. DePoy·R. P. Kirshner·J. Parrent
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Abstract

Spectra and light curves of SN 2006gz show the strongest signature of unburned carbon and one of the slowest fading light curves ever seen in a type Ia event (Delta m_15 = 0.69 +/- 0.04). The early-time Si II velocity is low, implying it was slowed by an envelope of unburned material. Our best estimate of the luminosity implies M_V = -19.74 and the production of ~ 1.2 M_sun of 56Ni. This suggests a super-Chandrasekhar mass progenitor. A double degenerate merger is consistent with these observations.

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M. Hicken, P. M. Garnavich, J. L. Prieto, S. Blondin, D. L. DePoy, R. P. Kirshner, J. Parrent. 2007-09-11. The Luminous and Carbon-Rich Supernova 2006gz: A Double Degenerate Merger?. https://doi.org/10.1086/523301

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