High velocity water maser emission from the Post-AGB star OH 009.1-0.4

A. J. Walsh; S. L. Breen; I. Bains; W. H. T. Vlemmings

paper

High velocity water maser emission from the Post-AGB star OH 009.1-0.4

arXiv:0812.1832

Abstract

Observations of H $_{2}$ O masers towards the post-AGB star and water fountain source OH 009.1--0.4 were made as part of HOPS (The H $_{2}$ O southern galactic Plane Survey), with the Mopra radiotelescope. Together with followup observations using the Australia Telescope Compact Array (ATCA), we have identified H $_{2}$ O maser emission over a velocity spread of nearly 400km/s (--109 to +289km/s). This velocity spread appears to be the largest of any known maser source in our Galaxy. High resolution observations with the ATCA indicate the maser emission is confined to a region $0\farcs3 \times 0\farcs3$ and shows weak evidence for a separation of the red- and blueshifted maser spots. We are unable to determine if the water fountain is projected along the line of sight, or is inclined, but either way OH 009.1--0.4 is an interesting source, worthy of followup observations.

Accepted by MNRAS Lett