Study of laser produced plasmas from boron, carbon and boron carbide Targets.
06-05-2015 07:23
ABSTRACT: Spectroscopic investigations were made on plasma clouds created by 20 ns, 3 J ruby laser pulses impinging perpendicularly onto targets of boron carbide, carbon and boron. The irradiance on the targets was about 132 GW cm-2. Time-resolved spectra of plasmas in the region of wavelength from 16 to 32 nm were observed at a distance of 1 mm from the targets. The maximum electron temperatures were about 60 eV in the case of carbon and boron targets, and about 45 eV in the case of boron-carbide target. Laser evaporation from carbon occurred directly from the solid state (sublimation), and in the case of a boron and boron-carbide melting was observed as an intermediate state.