Evolution of Powerful H2O Maser Flares in the Active Star Formation Region W51
Tóm tắt
Results of a study of powerful H2O maser flares in the W51 region from observations (monitoring) in 2009–2022 with the 22-m radio telescope in the Pushchino Radio Astronomy Observatory are presented. Three powerful maser flares were detected at radial velocities of 69.7, 61.6, and 59.0 km/s with flux densities at peaks of 23.1, 29.4, and 66.1 kJy, respectively. The first and third of them are identified with the main source (W51 Main). A probable reason for their occurrence may be the superposition of two maser condensations with close radial velocities on the line of sight. A large number of flares with flux densities above 10 kJy were also detected, most of which were identified with W51 North. The mechanism for the appearance of the asymmetry of the line for the most powerful flare at a radial velocity of 59 km/s is discussed.
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