Interaction of laser radiation with matter

Study of the emission spectra of Cl-, Br-, I-containing targets in the spectral range of 3–6.5 nm when excited by pulsed laser radiation

V. E. Guseva, S. A. Garakhin, A. N. Nechai, A. A. Perekalov, N. N. Tsybin, N. I. Chkhalo

Institute for Physics of Microstructures, Russian Academy of Sciences, Nizhnii Novgorod

Abstract: The results of studying the emission spectra of Cl-, Br-, and I-containing liquid-jet targets in the wavelength range of 3 – 6.5 nm when excited by pulsed laser radiation are described. A number of emission lines of Cl, Br, I ions were registered, including those in the range of the "water transparency window" 2.3 - 4.4 nm. A specially developed system based on the industrial impulse valve was used to form a liquid-jet target. The targets were excited by a Nd:YAG laser (λ 1064 nm, τ = 5.2 ns, E_pulse = 0.8 J). Using a Bragg spectrometer based on a multilayer Cr/Sc X-ray mirror and Ti/Be absorption filters, we measured the absolute intensities of some of the most intense lines. The high emissivity of liquid targets was demonstrated. Thus, for a bromine-containing target in the 6.12 ± 0.05 nm band, the resulting radiation intensity into the half-space was 1.3 × 10¹³ photon/pulse.

Keywords: gas jets, soft x-rays, extreme ultraviolet radiation, emission spectra, laser spark.

Received: 20.02.2023
Revised: 13.04.2023

 English version: Quantum Electronics, 2023, 50:suppl. 9, S1042–S1049