Accession Number : AD0694363

Title :   THE Cl + HBr PULSED CHEMICAL LASER - A THEORETICAL AND EXPERIMENTAL STUDY.

Descriptive Note : Research rept.,

Corporate Author : AVCO EVERETT RESEARCH LAB EVERETT MASS

Personal Author(s) : Airey,J. Richard

Report Date : AUG 1969

Pagination or Media Count : 44

Abstract : The most powerful and efficient pulsed chemical lasers produced to date have resulted from the simple exothermic reactions between halogen atoms and hydrogen halides. These reactions have been initiated by flash photolysis. One such reaction is: Cl + HBr yields HCl + Br; -delta H = 15.5 Kcal/mole. A kinetic model has been developed for this laser system which calculates the intensity profile of the laser pulse as a function of time. The input data for the model includes estimates of the reaction rate into the specific vibrational levels of HCl and cross sections for collisional deactivation by the different chemical species in the laser medium. The theoretical model also requires as input data the photolysis flash intensity profile, the cavity geometry, and the losses. A discussion of the model is given and a comparison is made between experiment and theory. The model is able to predict quantitative variations of the laser pulse characteristics as a function of flash intensity, cavity losses, and reagent partial pressures. The quantitative calculations are in reasonable agreement with experiment. It is concluded that, (a) the most important single contribution to deactivation in the system is: HCl (V = 1) + HBr (V = O) yields HCl (V = O) + HBr (V - 1); and (b) the rate of reaction to produce HCl (V = 1) is at least as large as that to produce HCl (V = 0). (Author)

Descriptors :   (*PHOTOCHEMICAL REACTIONS, *GAS LASERS), (*CHLORINE, GAS LASERS), PHOTOLYSIS, BROMINE COMPOUNDS, BROMINE, HYDROGEN COMPOUNDS, MATHEMATICAL MODELS, MOLECULAR ENERGY LEVELS, INFRARED PULSES

Subject Categories : Radiation and Nuclear Chemistry
      Lasers and Masers

Distribution Statement : APPROVED FOR PUBLIC RELEASE