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The fine spatial structure of methanol masers as an evidence in support of their connection with bipolar outflows

V. I. Slysh·I. E. Val'tts·S. V. Kalenskii
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Abstract

We studied class I methanol masers in the transition 7_0-6_1 A+ at the frequency 44 GHz with the VLA. The observations on the VLA were made with the angular resolution 0''.1, which was the highest at the moment. It was shown that the masers consist of chains of unresolved spots located on curved lines or arcs. The length of such arcs is from 20 to 1000 AU and the brightness temperature of the strongest masers exceeds 3.6x10^8 K. The observed location of maser spots is in agreement with their position at the border line between molecular outflows and surrounding molecular clouds. The high brightness temperature implies that the maser condensations have enhanced abundance of methanol due to evaporation of methanol from the surface of dust grains. The mass of maser condensations is less than 4x10^-5 solar mass and corresponds to planetary masses.

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V. I. Slysh, I. E. Val'tts, S. V. Kalenskii. 2001-05-24. The fine spatial structure of methanol masers as an evidence in support of their connection with bipolar outflows. https://arxiv.org/abs/astro-ph/0105436

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