The 6-GHz methanol multibeam maser catalogue – I. Galactic Centre region, longitudes 345° to 6°
MetadataShow full item record
We have conducted a Galactic plane survey of methanol masers at 6668 MHz using a seven-beam receiver on the Parkes telescope. Here we present results from the first part, which provides sensitive unbiased coverage of a large region around the Galactic Centre. Details are given for 183 methanol maser sites in the longitude range 345° through the Galactic Centre to 6°. Within 6° of the Galactic Centre, we found 88 maser sites, of which more than half (48) are new discoveries. The masers are confined to a narrow Galactic latitude range, indicative of many sources at the Galactic Centre distance and beyond, and confined to a thin disc population; there is no high-latitude population thatmight be ascribed to the Galactic bulge. Within 2° of the Galactic Centre the maser velocities all lie between -60 and +77kms-1, a range much smaller than the 540kms-1 range observed in CO.Elsewhere, the maser with highest positive velocity (+107kms-1) occurs, surprisingly, near longitude 355° and is probably attributable to the Galactic bar. The maser with the most negative velocity (-127kms-1) is near longitude 346°, within the longitude-velocity locus of the near side of the `3-kpc arm'. It has the most extreme velocity of a clear population of masers associated with the near and far sides of the 3-kpc arm. Closer to the Galactic Centre the maser space density is generally low, except within 0.25 kpc of the Galactic Centre itself, the `Galactic Centre zone', where it is 50 times higher, which is hinted at by the longitude distribution, and confirmed by the unusual velocities.
Showing items related by title, author, creator and subject.
The 6-GHz multibeam maser survey - II. Statistical analysis and Galactic distribution of 6668-MHz methanol masersGreen, J.; Breen, S.; Fuller, G.; McClure-Griffiths, N.; Ellingsen, S.; Voronkov, M.; Avison, A.; Brooks, K.; Burton, M.; Chrysostomou, A.; Cox, J.; Diamond, P.; Gray, M.; Hoare, M.; Masheder, M.; Pestalozzi, M.; Phillips, C.; Quinn, L.; Richards, A.; Thompson, M.; Walsh, Andrew; Ward-Thompson, D.; Wong-McSweeney, D.; Yates, J. (2017)The Methanol Multibeam survey has produced the largest and most complete census of methanol and excited-state hydroxyl masers in the Galaxy to date. Observing the entire Galactic plane visible from the Southern hemisphere ...
Purcell, C.; Longmore, S.; Walsh, Andrew; Whiting, M.; Breen, S.; Britton, T.; Brooks, K.; Burton, M.; Cunningham, M.; Green, J.; Harvey-Smith, L.; Hindson, L.; Hoare, M.; Indermuehle, B.; Jones, P.; Lo, N.; Lowe, V.; Phillips, C.; Thompson, M.; Urquhart, J.; Voronkov, M.; White, G. (2012)The H2O Southern Galactic Plane Survey (HOPS) has mapped a 100° strip of the Galactic plane (-70° > l > 30°, |b| < 0°.5) using the 22 m Mopra antenna at 12 mm wavelengths. Observations were conducted in on-the-fly mode ...
Qiao, H.; Walsh, Andrew; Shen, Z.; Dawson, J. (2016)Ground-state OH masers identified in the Southern Parkes Large-Area Survey in Hydroxyl were observed with the Australia Telescope Compact Array to obtain positions with high accuracy (~1 arcsec). We classified these OH ...