Astrophysical Lasers with Radiation Pumping by Accidental Resonance

Abstract:
In this paper we consider a general problem of astrophysical lasersoperating with optical pumping by accidental resonance (PAR) with strongspontaneous emission lines of other elements. The origin of populationinversion and the coefficient of amplification due to the opticalexcitation of atoms (ions) by a four-level scheme with PAR are analyzed.We elucidate conclusively the question of the manifestation ofastrophysical lasers in the optical region of the spectrum, which inprinciple differs from that of astrophysical masers in the microwaverange.