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arXiv · 1901.11235

A 3D view of molecular hydrogen in Supernova 1987A

J. Larsson·J. Spyromilio·C. Fransson·R. Indebetouw·M. Matsuura·F. J. Abellan·P. Cigan·H. Gomez·B. Leibundgut
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Abstract

Supernova (SN) 1987A is the only young SN in which H_2 has been detected in the ejecta. The properties of the H_2 are important for understanding the explosion and the ejecta chemistry. Here, we present new VLT/SINFONI observations of H_2 in SN 1987A, focussing on the 2.12 \mu m (1,0)S(1) line. We find that the 3D emissivity is dominated by a single clump in the southern ejecta, with weaker emission being present in the north along the plane of the circumstellar ring. The lowest observed velocities are in the range 400-800 km/s, in agreement with previous limits on inward mixing of H. The brightest regions of H_2 coincide with faint regions of H\alpha, which can be explained by H\alpha being powered by X-ray emission from the ring, while the H_2 is powered by 44Ti. A comparison with ALMA observations of other molecules and dust shows that the brightest regions of H_2, CO and SiO occupy different parts of the inner ejecta and that the brightest H_2 clump coincides with a region of very weak dust emission. The latter is consistent with theoretical predictions that the H_2 should form in the gas phase rather than on dust grains.

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J. Larsson, J. Spyromilio, C. Fransson, R. Indebetouw, M. Matsuura, F. J. Abellan, P. Cigan, H. Gomez, B. Leibundgut. 2019-01-31. A 3D view of molecular hydrogen in Supernova 1987A. https://doi.org/10.3847/1538-4357/ab03d1

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