Affiliation:
1. Crimean Astrophysical Observatory
2. Lebedev Physical Institute, Russian Academy of Sciences
Abstract
Based on long-term monitoring of the water vapor maser at 22.2 GHz from early 2019 to March 2021, the most powerful flare event in the entire history of observations was recorded in the protostellar system IRAS 16293-2422 at a velocity of about –1.5 km s–1, lasting of about two years. The maser emission came from the largest structure of maser spots, the high density of which created their partial overlap in time. The total number of individual flares of the water maser reached ten. Due to the high detail of the data obtained, recorded at intervals of 1–2 days, new unique results were obtained. The existence of such a complex configuration of emitting maser spots with very similar radial velocities located on the observer’s line of sight was confirmed for the first time. It was possible to establish that the masers of powerful flares were in an un-saturated state due to the cascade pumping of several masers on the observer’s line of sight. New important parameters of water masers have been obtained, and an assumption has been made about their localization in the gas-dust structure IRAS 16293-2422.
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