Investigation Of Laser Interaction Research Articles

Investigation of laser interaction with tungsten target by means of time-resolved optical spectroscopy

The paper reports on space- and time-resolved spectroscopic measurements performed during the interaction of an intense laser pulse (0.7 J, 2 ns) with a tungsten target, which was located inside a vacuum chamber. The optical spectra were recorded with a Mechelle®900 optical spectrometer and a CCD camera coupled with a computer equipped with the GRAMS32-v.6.0 software. Spectral lines emitted by excited tungsten atoms and single-charged tungsten ions were identified and analyzed. Using a two-step procedure for fitting the line profile, it was possible to estimate parameters of a tungsten plasma plume formed in the front of the investigated target. The appearance of the tungsten ions was also confirmed by measurements performed with an electrostatic ion-energy analyzer.

Investigations of laser interaction with high-Z targets

This article presents the tendency of the changes of Nd-laser plasma parameters in dependence upon increasing target atomic numbers. In the experiment, the following targets — (C8H8)n, SiO2, Al, Cu, Ta, and Au — were investigated. For targets with Z higher than 13, the two-temperature plasma is observed with temperatures Te =500–600 eV and Te≅ 100 eV. Energy carried by ions from the low-temperature plasma can be higher than half the total energy carried by ions. The number of ions from low-temperature, X-ray-heated plasma can be by an order of magnitude higher than the number of ions from thermal plasma (Te = 500–600 eV).