Spectroscopic evaluation of electron density and temperature of a laser plasma source in the vacuum ultraviolet

M. A. Khater; E. T. Kennedy

doi:10.1140/epjp/i2012-12061-7

EPJ

Spectroscopic evaluation of electron density and temperature of a laser plasma source in the vacuum ultraviolet

M. A. Khater¹^* and E. T. Kennedy²

¹ Department of Physics, College of Science, Al-Imam Muhammad Ibn Saud Islamic University, Riyadh, KSA
² School of Physical Sciences, Dublin City University, Dublin 9, Ireland

Received: 9 April 2012
Accepted: 21 May 2012
Published online: 4 June 2012

Abstract

A time-integrated space-resolved emission spectroscopic technique was developed in the VUV spectral range for the measurement of the electron number density and excitation temperature of laser-produced steel plasmas. 400 mJ pulses of Nd:YAG laser (7 ns duration) emitted at the fundamental wavelength of 1.06 μm are used to create the steel plasmas under moderate vacuum conditions (∼ 0.2 mbar). The electron number density was estimated from measurements of the FWHM of the Stark-broadened C II 68.73nm carbon spectral line. The excitation temperature was evaluated by the Boltzmann’s plot method for five selected Fe III iron spectral lines in the wavelength range 89-93nm.