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A Search for Extragalactic Methanol Masers

S. P. Ellingsen·R. P. Norris·J. B. Whiteoak·R. A. Vaile·P. M. McCulloch·M. Price
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Abstract

A sensitive search for 6.7--GHz methanol maser emission has been made towards 10 galaxies that have yielded detectable microwave molecular--line transitions. These include several which show OH megamaser or superluminous \water\/ maser emission. Within the Galaxy, \methanol\/ and OH masers often occur in the same star formation regions and, in most cases, the \methanol\/ masers have a greater peak flux density than their OH counterparts. Thus we might expect \methanol\/ masers to be associated with extragalactic OH maser sources. We failed to detect any emission or absorption above our 60--mJy detection limit. We conclude that if the physical conditions exist to produce \methanol\/ megamaser emission, they are incompatible with the conditions which produce OH megamaser emission.

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S. P. Ellingsen, R. P. Norris, J. B. Whiteoak, R. A. Vaile, P. M. McCulloch, M. Price. 1994-03-28. A Search for Extragalactic Methanol Masers. https://doi.org/10.1093/mnras%2F267.3.510

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