# Detection of HC$_3$N maser emission in NGC253

## TL;DR

This paper reports the first detection of HC3N maser emission in an extragalactic source, specifically in NGC253, revealing new insights into molecular gas dynamics in starburst galaxies.

## Contribution

It presents the first detection of HC3N maser emission in NGC253, expanding understanding of molecular masers in extragalactic environments.

## Key findings

- HC3N maser emission detected at 36.4 GHz with brightness temperature over 2500 K.
- Maser emission offset from galaxy center, near a methanol maser.
- Masers located at the interface of the galactic bar and central molecular zone.

## 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.