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Investigations of the Class I methanol masers in NGC 4945
journal contribution
posted on 2023-05-19, 21:06 authored by Tiege McCarthyTiege McCarthy, Simon EllingsenSimon Ellingsen, Breen, SL, Henkel, C, Voronkov, MA, Chen, XWe have used the Australia Telescope Compact Array (ATCA) to conduct further observations of the 36.2-GHz (4−1 → 30E) methanol transition towards the nearby active galaxy NGC 4945. These observations have led to a more accurate determination of the offset between the maser emission and the nucleus of NGC 4945 with a typical synthesized beam of 6 arcsec × 4 arcsec (108 × 72 pc). This corresponds to a factor of 4 improvement with respect to the major axis of the beam. Other transitions of methanol and lines of other molecular species were obtained alongside the 36.2-GHz methanol emission, with strong detections of HC3N (J = 4 → 3) and CS (J = 1 → 0) presented here. We do not detect thermal methanol (5σ upper limit of 5 mJy in a 6 km s−1 channel) from the 48.4-GHz (10 → 00A+) ground-state transition, nor emission from the 44.1-GHz (70 → 61A+) class I maser transition (5σ upper limit of 6 mJy in a 3 km s−1 channel). We also present a comparison of the class I maser emission observed towards NGC 4945 with that from NGC 253 and towards the Galactic giant molecular cloud G 1.6-0.025.
History
Publication title
Monthly Notices of the Royal Astronomical SocietyVolume
480Pagination
4578-4588ISSN
0035-8711Department/School
School of Natural SciencesPublisher
Blackwell Publishing LtdPlace of publication
9600 Garsington Rd, Oxford, England, Oxon, Ox4 2DgRights statement
Copyright 2018 The Author(s)Repository Status
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