Publication Date:
2015-09-16
Description:
We performed a 22 GHz H 2 O maser survey towards 221 Bolocam Galactic Plane Survey (BGPS) sources. We detected 107 H 2 O masers, of which 12 are new. The detection rate is 48.4 per cent for our sample. We obtained the positions of five new H 2 O masers via On The Fly (OTF) observations. The detection rate of H 2 O masers is correlated with continuum emission fluxes of BGPS sources at far-infrared, sub-millimetre and millimetre wavelengths. We employed the classification of Dunham et al. to classify the evolutionary stage of BGPS sources into Group 0, 1, 2, and 3. The detection rate and velocity range of H 2 O masers increases as the BGPS sources evolve from Group 1 to Group 3. The BGPS sources associated with both H 2 O and CH 3 OH masers are more compact than that associated with either only H 2 O or only CH 3 OH masers. This indicates that the sources associated with both H 2 O and CH 3 OH masers are in relative later evolutionary stage. The detection rate of H 2 O masers towards BGPS sources displaying evidence of the collapse phenomenon is 62.1 per cent, which suggests that most BGPS sources showing indications of collapse phenomena contain ongoing active star formation activities.
Print ISSN:
0035-8711
Electronic ISSN:
1365-2966
Topics:
Physics
