2012/11/05 by Christopher H. Jordan, C. Jordan, Andrew Walsh +9
Chemistry · Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Atomic physics #Emission spectrum #Excited state #Galactic plane #Galaxy #Line (geometry) #Maser #Millimeter #Molecular Spectroscopy and Structure #Molecular cloud #Physics #Radio telescope #Spectral line #Spectral resolution #Stars #Stellar, planetary, and galactic studies #Telescope #astro-ph.GA
paper · pdf · doi:10.1093/mnras/sts350
Accepted by MNRAS on November 2, 2012
arxiv created 2012/11/05 · openalex publication_date 2012/12/01 · arxiv updated 2015/06/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We introduce the Millimetre Astronomer’s Legacy Team – 45 GHz (MALT-45) Galactic plane survey and describe pilot survey results with the Australia Telescope Compact Array (ATCA). The pilot survey was conducted to test the instrumentation and observational technique of MALT-45, before commencing the full survey. We mapped two half-square degree regions within the southern Galactic plane around the G333 giant molecular cloud, using fast mosaic mapping. Using the new Compact Array Broad-band Backend on the ATCA, we were able to observe two 2048 MHz spectral windows, centred on frequencies 43.2 and 48.2 GHz. Although only a coarse spectral resolution of around 7 km s−1 was available to us, we detect widespread, extended emission in the CS (1–0) ground state transition. We also detect eight Class I CH3OH masers at 44 GHz and three SiO masers in vibrationally excited (1–0) transitions. We also detect the H53α radio recombination line, non-vibrationally excited SiO (1–0) and emission in the CH3OH 11–00 A+ line.