Facial reconstruction

Search LJMU Research Online

Browse Repository | Browse E-Theses

MALT-45: a 7 mm survey of the southern Galaxy - I. Techniques and spectral line data

Jordan, CH, Walsh, AJ, Lowe, V, Voronkov, MA, Ellingsen, SP, Breen, SL, Purcell, CR, Barnes, PJ, Burton, MG, Cunningham, MR, Hill, T, Jackson, JM, Longmore, SN, Peretto, N and Urquhart, JS (2015) MALT-45: a 7 mm survey of the southern Galaxy - I. Techniques and spectral line data. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 448 (3). pp. 2344-2361. ISSN 0035-8711

1501.06650v2.pdf - Accepted Version

Download (4MB) | Preview
Publisher URL: http://dx.doi.org/


We present the first results from the MALT-45 (Millimetre Astronomer's Legacy Team-45 GHz) Galactic Plane survey. We have observed 5 square degrees (l = 330°–335°, b = ±0 ∘ . 5) for spectral lines in the 7 mm band (42–44 and 48–49 GHz), including CS (1–0), class I CH3OH 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 CH3OH 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 CH3OH masers were associated with the published locations of class II CH3OH, H2O and OH masers but 42 have no known masers within 60 arcsec. We compared the MALT-45 CS with NH3 (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 NH3. 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.

Item Type: Article
Additional Information: This is a pre-copyedited, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The version of record; 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. (2015) MALT-45: a 7 mm survey of the southern Galaxy - I. Techniques and spectral line data, is available online at: http://dx.doi.org/10.1093/mnras/stv178 .
Uncontrolled Keywords: 0201 Astronomical And Space Sciences
Subjects: Q Science > QB Astronomy
Divisions: Astrophysics Research Institute
Related URLs:
Date Deposited: 27 May 2015 11:20
Last Modified: 04 Sep 2021 14:19
DOI or ID number: 10.1093/mnras/stv178
URI: https://researchonline.ljmu.ac.uk/id/eprint/1312
View Item View Item