MALT-45, a 7mm survey of the southern Galaxy

DOI

We present the first results from the MALT-45 (Millimetre Astronomer's Legacy Team-45GHz) Galactic Plane survey. We have observed 5 square degrees (l=330{deg}-335{deg}, b=+/-0.5{deg}) for spectral lines in the 7mm band (42-44 and 48-49GHz), including CS (1-0), class I CH_3_OH masers in the 7(0,7)-6(1,6) A^+^ transition and SiO (1-0) v=0,1,2,3. MALT-45 is the first unbiased, large-scale, sensitive spectral line survey in this frequency range. In this paper, we present data from the survey as well as a few intriguing results; rigorous analyses of these science cases are reserved for future publications. Across the survey region, we detected 77 class I CH_3_OH masers, of which 58 are new detections, along with many sites of thermal and maser SiO emission and thermal CS. We found that 35 class I CH_3_OH masers were associated with the published locations of class II CH_3_OH, H_2_O and OH masers but 42 have no known masers within 60 arcsec. We compared the MALT-45 CS with NH_3_ (1,1) to reveal regions of CS depletion and high opacity, as well as evolved star-forming regions with a high ratio of CS to NH_3_. All SiO masers are new detections, and appear to be associated with evolved stars from the Spitzer Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE). Generally, within SiO regions of multiple vibrational modes, the intensity decreases as v=1, 2, 3, but there are a few exceptions where v=2 is stronger than v=1.

Cone search capability for table J/MNRAS/448/2344/table2 (Properties of detected MALT-45 class I CH_3_OH maser emission (each maser was detected within a 64MHz zoom window))

Cone search capability for table J/MNRAS/448/2344/table3 (*Properties of detected MALT-45 SiO (1-0) maser emission (each maser was detected within a 64MHz zoom window))

Identifier
DOI http://doi.org/10.26093/cds/vizier.74482344
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/MNRAS/448/2344
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/448/2344
Related Identifier https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/448/2344
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/MNRAS/448/2344
Provenance
Creator Jordan C.H.; Walsh A.J.; Lowe V.; Voronkov M.A.; Ellingsen S.P.,Breen S.L.; Purcell C.R.; Barnes P.J.; Burton M.G.; Cunningham M.R.,Hill T.; Jackson J.M.; Longmore S.N.; Peretto N.; Urquhart J.S.
Publisher CDS
Publication Year 2018
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Galactic and extragalactic Astronomy; Interstellar medium; Natural Sciences; Observational Astronomy; Physics