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arXiv · 0805.1913

The type IIb SN 2008ax: the nature of the progenitor

Abstract

A source coincident with the position of the type IIb supernova (SN) 2008ax is identified in pre-explosion Hubble Space Telescope (HST) Wide Field Planetary Camera 2 observations in three optical filters. We identify and constrain two possible progenitor systems: (i) a single massive star that lost most of its hydrogen envelope through radiatively driven mass loss processes, prior to exploding as a helium-rich Wolf-Rayet star with a residual hydrogen envelope, and (ii) an interacting binary in a low mass cluster producing a stripped progenitor. Late time, high resolution observations along with detailed modelling of the SN will be required to reveal the true nature of this progenitor star.

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BibTeXRIS

R. M. Crockett, J. J. Eldridge, S. J. Smartt, A. Pastorello, A. Gal-Yam, D. B. Fox, D. C. Leonard, M. M. Kasliwal, S. Mattila, J. R. Maund, A. W. Stephens, I. J. Danziger. 2008-09-24. The type IIb SN 2008ax: the nature of the progenitor. https://doi.org/10.1111/j.1745-3933.2008.00540.x

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