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arXiv · 1005.0511

Type Ibc supernovae in disturbed galaxies: evidence for a top-heavy IMF

S. M. Habergham·J. P. Anderson·P. A. James
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Abstract

We compare the radial locations of 178 core-collapse supernovae to the R-band and H alpha light distributions of their host galaxies. When the galaxies are split into `disturbed' and `undisturbed' categories, a striking difference emerges. The disturbed galaxies have a central excess of core-collapse supernovae, and this excess is almost completely dominated by supernovae of types Ib, Ic and Ib/c, whereas type II supernovae dominate in all other environments. The difference cannot easily be explained by metallicity or extinction effects, and thus we propose that this is direct evidence for a stellar initial mass function that is strongly weighted towards high mass stars, specifically in the central regions of disturbed galaxies.

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S. M. Habergham, J. P. Anderson, P. A. James. 2010-05-04. Type Ibc supernovae in disturbed galaxies: evidence for a top-heavy IMF. https://doi.org/10.1088/0004-637x%2F717%2F1%2F342

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