Powerful masers at the early epochs

• Published in: Astrophysics and space science Vol. 171; no. 1-2; pp. 125 - 126
• Main Authors: Burdyuzha, V. V., Komberg, B. V.
• Format: Journal Article
• Language: English
• Published: 01-09-1990
• ISSN: 0004-640X; 1572-946X
• DOI: 10.1007/BF00646831

The sources of extra-Galactic OH megamasers are considered. It is argued that the appearance of an OH megamasar must fulfill the following conditions: there must be a powerful IR radiation at 53 microns, a turbulent motion of gas with V(turb) values between 5 km/sec and 0.7 km/sec, the temperature of the pumping radiation must be several times hgher than the kinetic temperature of molecules, and there must be a sufficient amount of 'inverted' molecules to realize the optical depth, tau, of about 1. For more powerful maser sources (i.e., with a solar luminosity of about 100,000), the optical depth must be at least 5 times greater than that in observed megamasers. It is shown that, for the optical depth to reach about 5, it is essential that either the luminosity of the pumping IR source is enhanced to 10 to the 13th solar luminosities, or that the column density of the inverted molecules is increased to N(OH) of about 5 x 10 to the 15th/sc cm. (I.S.)