A possible formation mechanism of the asymmetry in the H2O maser emission line

Authors :: N. A. Silant'ev
E. E. Lekht
A. M. Tolmachev
J. E. Mendosa-Torres
Source :: Astronomy Letters. 28:217-222
Publication Year :: 2002
Publisher :: Pleiades Publishing Ltd, 2002.
Abstract: We present a possible formation mechanism of the asymmetry in the maser emission line of H2O sources associated with star-forming regions. Observations with the RT-22 radio telescope at the Pushchino Radio Astronomy Observatory are used. We analyze the line profiles of emission features in the sources G43.8-0.1, NGC 2071, and ON1. If the line is asymmetric, the left (low-velocity) wing is higher than the right wing. The proposed mechanism accounts for the observed asymmetry and makes it possible to estimate some physical parameters of the medium in the vicinity of a maser spot.