Measurements of the Spectral Characteristics of the Laser-Plasma Sources Using Thermoluminescent Detectors

A method of wide-range X-ray and electron spectrometry of plasma formed by a femtosecond laser pulse with a peak intensity of over 1018 W/cm2 on the surface of a solid-state target is experimentally considered. Measurements of a flow of charged particles and quanta were carried out using thermoluminescent detectors based on LiF(Mg, Ti) that accumulate a dose, in front of which magnets were additionally installed to isolate the X-ray component. The spectra were obtained on the basis of the method for determining the accumulated dose of a detector depending on the thickness of the filter installed in front of it. The data have been restored in the range from 10 keV to several megaelectronvolts. The “temperatures” of the hot electron components of laser plasma have been determined, which are 160 and 1500 keV and may be related to the effects of particle acceleration in the dense-plasma region, as well as the temperatures during propagation of radiation in a cloud of subcritical density.