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arXiv · 1705.03080

Detection of HC$_3$N maser emission in NGC253

Simon Ellingsen·Xi Chen·Shari Breen·Hai-Hua Qiao
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Abstract

We report the detection of maser emission from the $J=4-3$ transition of HC$_3$N at 36.4~GHz towards the nearby starburst galaxy NGC253. This is the first detection of maser emission from this transition in either a Galactic or extragalactic source. The HC$_3$N maser emission has a brightness temperature in excess of 2500 K and is offset from the center of the galaxy by approximately 18 arcsec (300 pc), but close to a previously reported class~I methanol maser. Both the HC$_3$N and methanol masers appear to arise near the interface between the galactic bar and the central molecular zone, where it is thought that molecular gas is being transported inwards, producing a region of extensive low-velocity shocks.

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Simon Ellingsen, Xi Chen, Shari Breen, Hai-Hua Qiao. 2017-05-08. Detection of HC$_3$N maser emission in NGC253. https://doi.org/10.3847/2041-8213/aa71a6

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