High-time-resolution laser spectrometer

A pulsed laser spectrometer was developed on the basis of a tunable $He-Ar$ high-pressure laser. The accuracy of synchronizing the laser with an object being investigated was $\sim1$ nsec. In order to automate the measurements, pulse voltmeters having a wide dynamic range and devices for analog processing of the signals were developed. The spectrometer was used to investigate the characteristics of the $2p_{10}-1s_5$ transition in argon, in a nanosecond electric-discharge plasma. Measurements were made of the time dependence of the gain at the center of the transition and of the collisional broadening due to the helium (19 GHz/atm).