Nauchni, Simferopol, Russian Federation
Long-term monitoring data of the young protostellar source IRAS 16293-2422, having protoplanetary gas-dust disks, were obtained and analyzed. An uncommon in shape and duration flare, lasting about six months, consists of six short maser flares in an unsaturated state. The flares are at the top of the seventh, longer flare, which by its emission initiates the masers of six separate flares. Direct evidence has been obtained for the hypothesis of activation of water masers due to an increase in the length of the pumping path of masers during cascade amplification in maser spots located in the line of sight to the observer. In connection with the data obtained, the structural configuration of the source is considered.
star formations, stars with exoplanet, molecules, radio lines, water masers
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