Accurate water maser positions from HOPS
MetadataShow full item record
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.
Showing items related by title, author, creator and subject.
MALT-45: A 7mm survey of the southern Galaxy - II. ATCA follow-up observations of 44GHz class I methanol masersJordan, Christopher; Walsh, Andrew; Breen, S.; Ellingsen, S.; Voronkov, M.; Hyland, L. (2017)We detail interferometric observations of 44 GHz class I methanol masers detected by MALT-45 (a 7 mm unbiased auto-correlated spectral-line Galactic-plane survey) using the Australia Telescope Compact Array. We detect 238 ...
Qiao, H.; Walsh, Andrew; Green, J.; Breen, S.; Dawson, J.; Ellingsen, S.; Gómez, J.; Jordan, Christopher; Shen, Z.; Lowe, V.; Jones, P. (2016)We report on high spatial resolution observations, using the Australia Telescope Compact Array (ATCA), of ground-state OH masers. These observations were carried out toward 196 pointing centers previously identified in ...
High-mass star-forming cloud G0.38+0.04 in the Galactic center dust ridge contains H2CO and SiO masersGinsburg, A.; Walsh, Andrew; Henkel, C.; Jones, P.; Cunningham, M.; Kauffmann, J.; Pillai, T.; Mills, E.; Ott, J.; Kruijssen, J.; Menten, K.; Batersby, C.; Rathborne, J.; Contreras, Y.; Longmore, S.; Walker, D.; Dawson, J.; Lopez, J. (2015)We have discovered a new H2CO (formaldehyde) 11,0−11,1 4.82966 GHz maser in Galactic center Cloud C, G0.38+0.04. At the time of acceptance, this is the eighth region to contain an H2CO maser detected in the Galaxy. Cloud ...