Water Masers in the Star Forming Region G23.71-0.20

Star forming regions are sites where favorable physical conditions lead to gravitational collapse of molecular cores, resulting in the formation of protostellar systems and eventually new stars and planets. Masers have been found in star forming regions. Masers are characterized by intense microwave radiation due to population inversion and stimulated emission. Examples of maser species in massive star forming regions are water and formaldehyde. G23.71-0.20 is one of seven massive star forming regions in the Milky Way where both H2CO and H20 masers have been found. Han et al. (1998) reported a H2O maser at a velocity of -40.3km/s in G23.71-0.20, in contrast, the formaldehyde maser in the region is found at a velocity of 79.2km/s. The velocity difference between the two masers is quite significant (~120km/s) and suggests a high velocity outflow. We report a study intended to investigate water masers in G23.71-0.20. We did not detect the Han et al. (1998) maser, instead, H2O masers at 67.8km/s and 79.6km/s were found. We discuss the association of the water masers relative to the H2CO and other molecular masers in this region. Comparing our data with H2O maser measurements reported by Bartkiewicz et al. (2011), we find that H2O masers in this region are highly variable.