A theoretical study of the pulsed Cl₂ + HI chemical laser including nonequilibrium effects

In this study a new approach for handling the time evolution of the rotational distribution in a pulsed chemical laser is discussed. The suggested procedure assumes that the rotational distribution in each vibrational state during the lasing period can be described in any instant of time as a linear combination of known functions with time dependent coefficients. The evolution in time of these coefficients (three for each vibrational level) is given in terms of rate equations which are smoothly incorporated in the ordinary frame of the kinetic master equations. The method has been applied to the Cl₂ + HI pulsed chemical laser for which it is shown that the results obtained are similar to those we would expect from a treatment where each vibrational state is treated separately. In the preliminary study of the Cl₂ + HI system it is found that in the experimental setup used by Airey the photon yield is about 1.0 photons per HCl molecule.