1996/01/05 by S. P. Ellingsen, M. L. von Bibra, P. M. McCulloch +4 · 5 citations
Chemistry · Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Flux (metallurgy) #Galactic plane #Galaxy #Latitude #Longitude #Maser #Molecular Spectroscopy and Structure #Physics #Plane (geometry) #Range (aeronautics) #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1093/mnras/280.2.378
19 pages including 4 figures, using LaTeX formatted with mn.sty, accepted for publication in MNRAS
arxiv created 1996/01/05 · openalex publication_date 1996/05/11 · arxiv updated 2015/06/24 · openalex created_date 2019/11/22 · openalex updated_date 2026/08/05
We report the results of the first complete survey of an area of the Galactic plane for maser emission from the 6.7-GHz 51→60 A+ transition of CH3OH. The survey covers a 10.6-deg2 region of the Galactic plane in the longitude range 325° −335° and latitude range − 0####53−0####53. The survey is sensitive to masers with a peak flux density greater than ∼ 2.6 Jy. The weakest maser detected has a peak flux density of 2.3 Jy, and the strongest a peak flux density of 425 Jy. We detected a total of 50 distinct masers, 26 of which are new detections. We show that many 6.7-GHz CH3OH masers are not associated with IRAS sources, and that some are associated with sources that have colours differing from those of a typical ultracompact Hii (UCHii) region. We estimate that the number of UCH ii regions in the Galaxy is significantly more than suggested by IRAS-based estimates, possibly by more than a factor of 2.