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arXiv · 1401.6913

A sensitive search for methanol line emission toward evolved stars

J. F. Gomez·L. Uscanga·O. Suarez·J. R. Rizzo·I. de Gregorio-Monsalvo
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Abstract

We present a sensitive search for methanol line emission in evolved stars at 1 cm, aiming to detect, for the first time, methanol masers in this type of objects. Our sample comprised post-AGB stars and young planetary nebulae (PNe), whose mass-loss processes and circumstellar structures resemble those of young stellar objects (YSOs), where methanol masers are detected. Class I masers were searched for in 73 objects, whereas Class II ones were searched in 16. No detection was obtained. The non-detection of Class I methanol masers indicated that methanol production in dust grains and/or the enhancement of its gas-phase abundance in the shocked regions of evolved objects are not as efficient as in YSOs. We suggest that relatively more evolved PNe might have a better probability of harboring Class II masers.

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J. F. Gomez, L. Uscanga, O. Suarez, J. R. Rizzo, I. de Gregorio-Monsalvo. 2014-03-04. A sensitive search for methanol line emission toward evolved stars. https://arxiv.org/abs/1401.6913

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