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arXiv · 1004.3329

The Exceptionally Luminous Type Ia Supernova 2007if

F. Yuan·R. M. Quimby·J. C. Wheeler·J. Vinko·E. Chatzopoulos·C. W. Akerlof·S. Kulkarni·J. M. Miller·T. A. McKay·F. Aharonian
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Abstract

SN 2007if was the third over-luminous SN Ia detected after 2003fg and 2006gz. We present the photometric and spectroscopic observations of the supernova and its host by ROTSE-III, HET and Keck. From the H_alpha line identified in the host spectra, we determine a redshift of 0.0736. At this distance, the supernova reached an absolute magnitude of -20.4, brighter than any other SNe Ia ever observed. If the source of luminosity is radioactive decay, a large amount of radioactive nickel (~1.5 solar masses) is required to power the peak luminosity, more than can be produced realistically in a Chandrasekhar mass progenitor. Low expansion velocity, similar to that of 2003fg, is also measured around the maximum light. The observations may suggest that SN 2007if was from a massive white dwarf progenitor, plausibly exploding with mass well beyond 1.4 solar masses. Alternatively, we investigate circumstellar interaction that may contribute to the excess luminosity.

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F. Yuan, R. M. Quimby, J. C. Wheeler, J. Vinko, E. Chatzopoulos, C. W. Akerlof, S. Kulkarni, J. M. Miller, T. A. McKay, F. Aharonian. 2010-04-28. The Exceptionally Luminous Type Ia Supernova 2007if. https://doi.org/10.1088/0004-637x%2F715%2F2%2F1338

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