A sensitive search for water masers associated with star formation regions in the Local Group galaxy NGC 6822

TL;DR

This study conducted a sensitive search for water masers in NGC 6822, tentatively detecting four candidates linked to star-forming regions, providing insights into maser activity in nearby galaxies.

Contribution

First sensitive search for water masers in NGC 6822, identifying tentative detections and refining previous non-detections with higher sensitivity.

Findings

Tentative detections of four water maser candidates.

Candidates are offset from HI gas velocity range.

No detection at previous tentative maser location with improved sensitivity.

Abstract

We report the results of a sensitive search for water maser emission in the Local Group Galaxy NGC 6822 with the Karl G. Jansky Very Large Array. The observations provide tentative single-epoch detections of four candidates, associated with two infrared-bright star formation regions (Hubble I/III and Hubble IV). The candidate maser detections are all offset from the velocity range where strong emission from HI neutral gas is observed toward NGC 6822, with the closest offset by 40 kms$^{-1}$. Our observations include the location of NL1K, a previous tentative water maser detection in NGC 6822. We do not detect any emission from this location with a sensitivity limit approximately a factor of 5 better than the original Sardina Radio Telescope observations.