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arXiv · 1902.02249

Titanium hidden in dust

A. Iyudin·E. Müller·M. Obergaulinger
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Abstract

Cassiopeia A, one of the most intriguing galactic supernova remnants, has been a target of many observational efforts including most recent observations by ALMA, Hubble, Herschel, Spitzer, NuSTAR, Integral, and other observatories. We use recent gamma-ray lines observations of the radioactive products of Cas A supernova explosive nucleosynthesis as well as spectral energy densities derived for Cas A at infrared wavelengths to speculate about the possibility of radioactive 44Ti being locked into large dust grains. This suggestion is also supported by the possible observation of a pre-supernova outburst about 80 years before the actual Cas A supernova explosion in 1671 AD by Italian astronomer G.D. Cassini. The plausibility of such a scenario is discussed also with reference to recent supernovae, and to the contribution of core-collapse supernovae to the overall dust production in the Galaxy.

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A. Iyudin, E. Müller, M. Obergaulinger. 2019-02-06. Titanium hidden in dust. https://doi.org/10.1093/mnras%2Fstz419

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