H2O Masers in the Galactic Plane. I. Longitude 340º to the Galactic Centre

Abstract

Twenty-five new H20 masers in the southern galactic plane have been discovered using a 22 GHz maser receiver on the Parkes telescope. The search was conducted at the locations of all the known 1665 MHz OH masers in the longitude range 340° through the galactic centre to 2°; of the 46 type I OH masers 38 are now found to have an H20 maser nearby; three other main-line OH emitters, possibly unusual late-type stars, also show H20 emission. We give an up-to-date tabulation of all 46 currently known H20 masers in the region which includes for completeness several H20 masers with no readily detectable associated type I OH emission.