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Protoplanetary disk in V645 Cyg as seen with H2O and methanol masers

I. E. Val'tts·V. I. Slysh·M. A. Voronkov·V. Migenes
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Abstract

Radio images of maser spots in the infrared source GL2789, connected with the young stellar object V645 Cyg, have been obtained as a result of the radio interferometric observations of H2O maser at 22 GHz and methanol maser at 6.7 GHz, with the VLBI arrays VLBA and EVN. It was shown that the position of the masers coincide with the optical object within 0.2''. The maser spots are located along the line North-South, and their position and radial velocity can be described by a model of the Keplerian disk with a maximum radius of 40 AU for H2O maser and 800 AU for methanol maser. The H2O and methanol maser spots have not been resolved, and lower limits of the brightness temperature is 2x10^{13} K and 1.4x10^9 K, respectively. A model of the maser was suggested in which the maser emission is generated in extended water and methanol envelopes of icy planets orbiting the young star.

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I. E. Val'tts, V. I. Slysh, M. A. Voronkov, V. Migenes. 2002-05-27. Protoplanetary disk in V645 Cyg as seen with H2O and methanol masers. https://arxiv.org/abs/astro-ph/0205452

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