Accurate water maser positions from HOPS
|dc.identifier.citation||Walsh, A. and Purcell, C. and Longmore, S. and Breen, S. and Green, A. and Harvey-Smith, L. and Jordan, C. et al. 2014. Accurate water maser positions from HOPS. Monthly Notices of the Royal Astronomical Society. 442 (3): pp. 2240-2252.|
We report on high spatial resolution water maser observations, using the Australia Telescope Compact Array, towards water maser sites previously identified in the H2O southern Galactic Plane Survey (HOPS). Of the 540 masers identified in the single-dish observations of Walsh et al., we detect emission in all but 31 fields. We report on 2790 spectral features (maser spots), with brightnesses ranging from 0.06 to 576 Jy and with velocities ranging from -238.5 to +300.5 km s-1. These spectral features are grouped into 631 maser sites. We have compared the positions of these sites to the literature to associate the sites with astrophysical objects. We identify 433 (69 percent) with star formation, 121 (19 percent) with evolved stars and 77 (12 percent) as unknown. We find that maser sites associated with evolved stars tend to have more maser spots and have smaller angular sizes than those associated with star formation. We present evidence that maser sites associated with evolved stars show an increased likelihood of having a velocity range between 15 and 35?km?s-1 compared to other maser sites. Of the 31 non-detections, we conclude they were not detected due to intrinsic variability and confirm previous results showing that such variable masers tend to be weaker and have simpler spectra with fewer peaks.
|dc.publisher||Oxford University Press|
|dc.title||Accurate water maser positions from HOPS|
|dcterms.source.title||Monthly Notices of the Royal Astronomical Society|
|curtin.department||Curtin Institute of Radio Astronomy|
|curtin.accessStatus||Open access via publisher|