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arXiv · 1302.0170

Supernova 2012ec: Identification of the progenitor and early monitoring with PESSTO

J. R. Maund·M. Fraser·S. J. Smartt·M. T. Botticella·C. Barbarino·M. Childress·A. Gal-Yam·C. Inserra·G. Pignata·D. Reichart·B. Schmidt·J. Sollerman·F. Taddia·L. Tomasella·S. Valenti·O. Yaron
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Abstract

We present the identification of the progenitor of the Type IIP SN 2012ec in archival pre-explosion HST WFPC2 and ACS/WFC F814W images. The properties of the progenitor are further constrained by non-detections in pre-explosion WFPC2 F450W and F606W images. We report a series of early photometric and spectroscopic observations of SN 2012ec. The r'-band light curve shows a plateau with M(r')=-17.0. The early spectrum is similar to the Type IIP SN 1999em, with the expansion velocity measured at Halpha absorption minimum of -11,700 km/s (at 1 day post-discovery). The photometric and spectroscopic evolution of SN 2012ec shows it to be a Type IIP SN, discovered only a few days post-explosion (<6d). We derive a luminosity for the progenitor, in comparison with MARCS model SEDs, of log L/Lsun = 5.15+/-0.19, from which we infer an initial mass range of 14-22Msun. This is the first SN with an identified progenitor to be followed by the Public ESO Spectroscopic Survey of Transient Objects (PESSTO).

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J. R. Maund, M. Fraser, S. J. Smartt, M. T. Botticella, C. Barbarino, M. Childress, A. Gal-Yam, C. Inserra, G. Pignata, D. Reichart, B. Schmidt, J. Sollerman, F. Taddia, L. Tomasella, S. Valenti, O. Yaron. 2013-02-01. Supernova 2012ec: Identification of the progenitor and early monitoring with PESSTO. https://doi.org/10.1093/mnrasl%2Fslt017

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