No Water Masers Associated with Supernova Remnants

Abstract

We have used the Very Large Array to search for water masers in the three supernova remnants W28, W44, and IC 443. Only one candidate maser was detected, in W44. Follow-up observations using the VLA at 1612 MHz demonstrate that the water maser in W44 is likely associated with a late-type star and not a shock in the supernova remnant. The nondetection of water masers toward shocked regions in these supernova remnants places constraints on the postshock density and is consistent with the density determined by molecular observations and the limits from 1720 MHz OH maser pumping.