Effect of laser light on matter. Laser plasmas

Measurements of the spectral characteristics of the laser-plasma sources using thermoluminescent detectors

K. A. Ivanov^ab, G. Kh. Salakhutdinov^c, A. I. Sivko^b, I. N. Tsymbalov^bd, I. G. Grigor'eva^c, I. A. Busigina^ce, A. A. Rupasov^a, P. V. Moskvich^e, R. V. Volkov^b, A. B. Savel'ev<sup>ab

a</sup> Lebedev Physical Institute, Russian Academy of Sciences, 119991, Moscow, Russia
^b Faculty of Physics, Lomonosov Moscow State University, 119991, Moscow, Russia
^c National Research Nuclear University MEPhI, 115409, Moscow, Russia
^d Institute of Nuclear Research, Russian Academy of Sciences, 117312, Moscow, Russia
^e Research and Development Institute of Scientific Instruments, 140080, Lytkarino, Moscow oblast, Russia

Abstract: 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.

Keywords: femtosecond laser plasma, thermoluminescent detectors, hot electrons, hard X-ray radiation, attenuation curve.

Received: 07.08.2024
Revised: 14.10.2024

 English version: Quantum Electronics, 2024, 51:suppl. 9, S720–S727