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arXiv · 1603.05560

Discovery of molecular hydrogen in SN 1987A

Claes Fransson·Josefin Larsson·Jason Spyromilio·Bruno Leibundgut·Richard McCray·Anders Jerkstrand
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Abstract

Both CO and SiO have been observed at early and late phases in SN 1987A. H_2 was predicted to form at roughly the same time as these molecules, but was not detected at early epochs. Here we report the detection of NIR lines from H_2 at 2.12 mu and 2.40 mu in VLT/SINFONI spectra obtained between days 6489 and 10,120. The emission is concentrated to the core of the supernova in contrast to H-alpha and approximately coincides with the [Si I]/[Fe II] emission detected previously in the ejecta. Different excitation mechanisms and power sources of the emission are discussed. From the nearly constant H_2 luminosities we favour excitation resulting from the 44Ti decay.

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Claes Fransson, Josefin Larsson, Jason Spyromilio, Bruno Leibundgut, Richard McCray, Anders Jerkstrand. 2016-03-17. Discovery of molecular hydrogen in SN 1987A. https://doi.org/10.3847/2041-8205/821/1/l5

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