Optics and Photonics Society of Iran

In this paper, electron temperature of a laser induced copper plasma experiment were measured using Optical Emission Spectroscopy (OES) by Boltzmann plot method. The plasma was produced in laser induced breakdown via the interaction of high power Nd:YAG laser operating at fundamental wavelength of 1064 nm and pulse duration ~10 ns with a plane solid copper target in ambient air. Five Cu I lines at 427.51 nm, 465.11 nm, 510.55 nm, 515.32 nm and 521.82nm are used for determination of electron temperature (T_^e). The electron temperature was determined for the condition of laser intensity varying from 5.21 to 18.231 GW/cm². The temperature was estimated using two different analyzing methods for emitted spectrum:  i) considering continuum emission and lines emissions of the spectrum and ii) removing the continuum contribution from the emitted spectrum and analyzing only the line emissions. The results show a small differences between the two approches.  According to our results within the applied laser pulse energy ranges, the estimated temperature increases from 10873 to 13342 K in the first approch and from 9705 to 10846 K for the second approach