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Exceptionally Bright Type Ib Supernova 1991D

S. Benetti·D. Branch·M. Turatto·E. Cappellaro·E. Baron·L. Zampieri·M. Della Valle·A. Pastorello
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Abstract

Photometric and spectroscopic observations of the peculiar Type Ib Supernova 1991D are presented. SN 1991D was exceptionally bright for a Type Ib supernova. The He I lines were rather weak and the velocity at the photosphere as a function of time was unusually low. Comparison of the observed and synthetic spectra indicates that either hydrogen was ejected with a minimum velocity of 12,000 km/s or the spectrum contained features caused by lines of Ne I. Light curve modelling suggests that the progenitor probably had a very large radius (~10^14 cm) and that a considerable amount of 56Ni was synthesized during the explosion (~0.7 Msolar). We suggest a progenitor model of SN 1991D that involves a binary system.

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S. Benetti, D. Branch, M. Turatto, E. Cappellaro, E. Baron, L. Zampieri, M. Della Valle, A. Pastorello. 2002-05-27. Exceptionally Bright Type Ib Supernova 1991D. https://doi.org/10.1046/j.1365-8711.2002.05706.x

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