Molecular-ion continua of the radiation emitted by rare gas plasmas

An investigation was made of the spectral and temporal characteristics of the continua of the radiation emitted by molecular ions in krypton, argon, and xenon excited by an electron beam and by x-ray pulses. An analysis was made of the dependences of the positions and relative intensities of local maxima of the rare-gas continua on the pressure, and on the pumping method and power. The role of transitions of dimer and trimer molecular ions in the generation of broad-band radiation was also considered. It was found that, under the investigated conditions, the properties of these continua are independent of the method of pumping by a hard ioniser, but are determined solely by the nature and pressure of the gas. It was shown that lasing as a result of transitions in molecular ions is most probable in the case of diatomic ions which as a rule have narrower individuals bands. For this purpose it is preferable to use high-density and short-duration electron-beam pulses with a rapid decay of the current.