The Medicina survey of methanol masers at 6.7 GHz

Abstract

A survey of Class II methanol masers at 6.7 GHz was made in the Northern hemisphere with the 32-m Medicina radio telescope. 42 objects were detected, 20 of them are new detections at 6.7 GHz. Our results show that the detection rate of 6.7 GHz masers toward the inner part of the Galaxy is higher than in other directions. It is conrmed that most of the methanol masers are as- sociated with faint compact HII regions. The 6.7 GHz me- thanol masers show large velocity dispersion and large ve- locity oset from the velocity of parent molecular clouds.