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arXiv · 1312.5024

12.2-GHz methanol maser MMB follow-up catalogue - III. Longitude range 10 to 20 degrees

Shari Breen·Simon Ellingsen·James Caswell·James Green·Maxim Voronkov·Adam Avison·Gary Fuller·Lyshia Quinn·Anita Titmarsh
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Abstract

We present the third instalment of a series of catalogues presenting 12.2-GHz methanol maser observations made towards each of the 6.7-GHz methanol masers detected in the Methanol Multibeam (MMB) Survey. The current portion of the catalogue includes the Galactic longitude region 10 to 20 degrees, where we detect 47 12.2-GHz methanol masers towards 99 6.7-GHz targets. We compare the occurrence of 12.2-GHz methanol masers with water maser emission, for which all 6.7-GHz methanol masers in the 6 to 20 degrees longitude range have now been searched. We suggest that the water masers follow a more complicated evolutionary scenario than has been found for the methanol and OH masers, likely due to their different pumping mechanisms. Comparisons of the 6.7-GHz methanol to OH maser peak flux density ratio and the luminosity of the associated 12.2-GHz sources suggests that the 12.2-GHz maser luminosity begins to decline around the time that an OH maser becomes detectable.

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Shari Breen, Simon Ellingsen, James Caswell, James Green, Maxim Voronkov, Adam Avison, Gary Fuller, Lyshia Quinn, Anita Titmarsh. 2013-12-18. 12.2-GHz methanol maser MMB follow-up catalogue - III. Longitude range 10 to 20 degrees. https://doi.org/10.1093/mnras%2Fstt2447

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