Sensitive OH observations towards 16 supernova remnants

Abstract

Sensitive observations made towards 16 supernova remnants in the 1.667-GHz OH line with the DRAO 26-m radio telescope are presented. These observations were made in a search for broad, asymmetric absorption features, such as that seen towards G189.1 +3.0 (IC443), in order to identify remnants which are interacting with molecular clouds and producing shock-excited species. Absorption by shocked OH is indicated in the cases of G33.6 + 0.1 and G84.2-0.8. Useful constraints on distances to several remnants are also derived.