Masers: Precision probes of molecular gas. Issue 2 (15th January 2020)

• Record Type: Journal Article
• Authors: Richards, A.M.S.; Sobolev, A.; Baudry, A.; Herpin, F.; Decin, L.; Gray, M.D.; Etoka, S.; Humphreys, E.M.L.; Vlemmings, W.
• Is Part Of: Advances in space research. Volume 65:Issue 2(2020)
• Page Start: 780
• Page End: 789
• Publication Date: 2020-01-15
• Subjects: Masers -- Stars: AGB -- Stars: supergiant -- Stars: mass loss -- Planetary systems: protoplanetary disks -- Star formation; Space sciences -- Periodicals; Astronautics -- Periodicals; Geophysics -- Periodicals; 500.505
• DOI: 10.1016/j.asr.2019.05.052
• Languages: English
• ISSNs: 0273-1177

Abstract

Abstract: Maser emission from water, methanol, silicon monoxide and other molecules can reach brightness temperatures ≫ 10 10 K. Such observations can achieve sub-pc precision for discs around black holes or sub-au scale interactions in protostellar discs and the regions where evolved star winds reach escape velocity. Ultra-high resolution maser observations also provide photon statistics, for fundamental physics experiments. RadioAstron has shown the success – and limitations – of cm-wave maser observations on scales ≪ 1 mas with sparse baseline coverage. ALMA, APEX and earlier single dish searches have found a wealth of mm and sub-mm masers, some of which probably also attain high brightness temperatures. Masers are ideal for high-resolution observations throughout the radio regime and we need to consider the current lessons for the best observational strategies to meet specific science cases.