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arXiv · 1411.1104

A young stellar environment for the superluminous supernova PTF12dam

C. C. Thöne·A. de Ugarte Postigo·R. García-Benito·G. Leloudas·S. Schulze·R. Amorín
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Abstract

The progenitors of super luminous supernovae (SLSNe) are still a mystery. Hydrogen-poor SLSN hosts are often highly star-forming dwarf galaxies and the majority belongs to the class of extreme emission line galaxies hosting young and highly star-forming stellar populations. Here we present a resolved long-slit study of the host of the hydrogen-poor SLSN PTF12dam probing the kpc environment of the SN site to determine the age of the progenitor. The galaxy is a "tadpole" with uniform properties and the SN occurred in a star-forming region in the head of the tadpole. The galaxy experienced a recent star-burst superimposed on an underlying old stellar population. We measure a very young stellar population at the SN site with an age of ~3 Myr and a metallicity of 12+log(O/H)=8.0 at the SN site but do not observe any WR features. The progenitor of PTF12dam must have been a massive star of at least 60 M_solar and one of the first stars exploding as a SN in this extremely young starburst.

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C. C. Thöne, A. de Ugarte Postigo, R. García-Benito, G. Leloudas, S. Schulze, R. Amorín. 2014-11-04. A young stellar environment for the superluminous supernova PTF12dam. https://arxiv.org/abs/1411.1104

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