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When Bromine is combined with flourine atoms and discharged oxygen in a flow tube is produced in a highly non thermal distribution peaking at v'=3. The emission was linearly dependent on the concentration. The observed dependence of the BrF(B) emission on Bromine and atomic oxygen is inconsistent with a steady state prediction of a sequential excitation mechanism, where BrF(X) is excited by successive collisions with singlet oxygen. The experimental data are consistent with a three body mechanism involving Br and F atoms. Electronic quenching of BrF(B) by a number of collision partners (Br2, CO2, O2, N2, CF4, SF6, Ar) was examined for three vibrational levels using laser induced fluorescence (LIF) techniques. Vibrational transfer in BrF(B), induced by the BrF production mix (CF4, Br2, F) was measured by observing the spectrally resolved LIF emission from each vibrational level after an initial excitation of BrF(B) v'=5.

The kinetic data base is extended for the A-state of BiF to include SF6 as a collision partner. By applying a four-level finite difference fitting routine to time-resolved fluorescence traces from v' = 0-3, one obtains rate coefficients for electronic quenching, as well as for vibrational relaxation within the A-state manifold. As was the case for our previous results with He and Ar, electronic quenching is slow in comparison to radiative decay. Vibrational relaxation does not show a simple v' dependence, but rather, for the levels examined, increases markedly for higher v'. Our results confirm the suitability of SF6 as a bulk diluent in the proposed NF/BiF chemical laser system.

Transient diffuser flow in an HF/DF laser is analyzed via a simplified model. A radial laser configuration is assumed where the diffuser is idealized as a ring-symmetric channel of uniform width. The outward radial flow following an abrupt start-up of diffuser inflow is computed numerically using a GRP-type code for integrating the Euler equations, which include an ongoing reaction of hydrogen recombination. A new kinetic scattering effect is suggested, resulting from the recoil of an HF or DF molecule assisting as third body in the hydrogen recombination reaction. The main conclusion is that transient diffuser plume flow effects do not drastically aggravate the potential for contaminating backflow (HF + DF) caused by either thermal or kinetic backscattering. Keywords: Laser exhaust; Spacecraft contamination; Chemical laser; Exhaust plume, Hydrogen recombination; Transient flow, Prepared for: Strategic Defense Initiatve Office The Pentagon, Washington, DC, http://archive.org/details/transientreactiv00falc

An efficient procedure for determining the operational potential of a laser system is the experimental measurement of gain. Two laser systems, a flowing CO₂-N₂-He laser and a chemical CO₂-HN₃, laser, were studied using a pulsed gain measurement technique. The experimental investigation indicated that the flowing CO₂-N₂ -He laser system could produce lasing action and that the saturation parameter was 15 watts/cm². The experimental results for the chemical laser show a gain of approximately 8% per meter and agree qualitatively with a computer model of the CO₂-HN₃ laser. However, difficulties in obtaining consistent results, which were attributed to saturation of the lasing medium by the reference signal, and a low signal-to- noise ratio prevented any final conclusion. Further experimental investigation of the CO₂-HN₃, laser will be necessary to determine the full potential of the laser system., http://archive.org/details/pulsedgainmeasur00houc, Ensign, United States Navy, Approved for public release; distribution is unlimited.

One of the most important methods of obtaining laser action, both from a technological and scientific viewpoint, is the chemically-pumped laser. The HN3 + C02 chemical laser has been modeled and an experimental investigation conducted to determine the existence of laser action. The analytical model has been used to predict the expected population inversion and laser gain for a range of pressures and various additives. The experimental investigation conducted for comparison with the model did not result in laser action. The increase in pressure for the mixtures investigated indicates the occurrence of an explosion. The lack of detection of laser action has been attributed to difficulties with alignment of the optical system and to signal noise associated with the flash circuit., http://archive.org/details/hn3co2laseranaly00helm, Lieutenant, United States Navy, Approved for public release; distribution is unlimited.

A small scale hydrogen fluoride (HF) or deuterium fluoride (DF) laser was constructed for the Atmospheric Optical Propagation Program at the Naval Postgraduate School. The laser, with almost forty individually selectable wavelengths between 2.5 and 4.1 micrometers, will prove to be a valuable instrument for the continued studies of laser propagation. In the HF mode, a multiline power out of seven watts was acheived with a confocal cavity arrangement. In the single-line HF mode, fifteen separate wavelengths were distinguished. Three watts of multiline power was achieved in the DF mode while eighteen separate single-line wavelengths were obtained including 160 milliwatts at 3.8007 micrometers, the P2(8) transition. This wavelength is of particular interest to the Navy because of its excellent propagation characteristics in the marine boundary layer., http://archive.org/details/ahydrogenfluorid1094541048, Lieutenant, United States Navy, Approved for public release; distribution is unlimited.

A small photochemical dissociation gas laser oscillator has been constructed for use in the study of laser characteristics, energy extraction techniques, and plasma production. It operates with a mixture of perfluorinated-propyliodide and argon as an active medium., http://archive.org/details/designndconstruc1094517722, Lieutenant, United States Navy, Approved for public release; distribution is unlimited.