Time-resolved spectral and energy characteristics of a pulsed nonchain HF laser

Investigations were made of the time-resolved spectral and energy characteristics of a C₃H₈–SF₆ laser using different active mixture pressures, chemical reaction initiation levels, and resonator parameters in both selective and nonselective lasing regimes. The measurements were performed using fast-response (≤ 0.5 nsec) pyroelectdc detectors. It was established that the laser pulses had a three-spike structure, resulting from lasing of the P lines in the following sequence: P₂→P₃→P₁. It was found possible to control the pulse shape and the spectral composition of the emitted radiation. An analytical model was proposed to explain the time sequence of lasing on the different vibrational transitions. An identification was made of the vibrational distributions of the laser pump reaction products for which other lasing time sequences are possible.