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arXiv · 2201.03723

Is FRB 191001 embedded in a supernova remnant?

Abstract

Fast radio burst (FRB) 191001 is localised at the spiral arm of a highly star-forming galaxy with an observed dispersion measure (DM) of 507 pc cm$^{-3}$. Subtracting the contributions of the intergalactic medium and our Milky Way Galaxy from the total DM, one gets an excess of around 200 pc cm$^{-3}$, which may have been contributed by the host galaxy of the FRB. It is found in this work that the position of FRB 191001 is consistent with the distribution of supernovae (SNe) in the spiral arm of their parent galaxies. If this event is indeed due to an SN explosion, then, from the analysis of the SN contributions to the excess DM, a core-collapse (CC) channel is preferred over a thermonuclear runaway. For the CC explosion, depending on the density of the surrounding medium, the age of the central engine that powers the radio burst is within a couple of years to a few decades. However, the observed rotation measure of FRB 191001 does not confirm the fact that the radio burst has passed through the remnant of a young SN.

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Esha Kundu. 2022-01-11. Is FRB 191001 embedded in a supernova remnant?. https://doi.org/10.1093/mnrasl%2Fslac003

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