A sensitive search for methanol line emission toward evolved stars

Autor:	Gomez, J. F., Uscanga, L., Suarez, O., Rizzo, J. R., de Gregorio-Monsalvo, I.
Rok vydání:	2014
Předmět:	Astrophysics - Galaxy Astrophysics Astrophysics - Solar and Stellar Astrophysics
Druh dokumentu:	Working Paper
Popis:	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. Comment: 11 pages, no figure. Accepted by Revista Mexicana de Astronomia y Astrofisica. Errors corrected during proof revision
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1401.6913 Zobrazit plný text záznamu View this record from Arxiv