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Abstract: We report the effect of the laser wavelength (1064, 532 and 355nm) and the ambient gas nature (argon, neon and helium) on the lead (Pb) plasma parameters produced by the Nd:YAG laser. The electron temperature and electron number density have been determined from the Boltzmann plots and Stark-broadened profiles of the spectral lines. It is found that the electron temperature and electron number density are the highest in the case of 355nm laser as compared to the 532nm and 1064nm lasers. At the laser irradiance of 3×1010 W/cm2 of 355nm laser, the spectral intensity of the Pb(I) 406.21nm transition line is about 3.7 times higher than that obtained with the 1064nm laser. The highest electron temperature and electron number density are obtained in the argon environment and the lowest in helium, while these plasma parameters decay faster in the helium environment. [Copyright &y& Elsevier]

We report measurements of the copper plasma parameters generated by the fundamental, second and third harmonics of a Nd:YAG laser. The 3d94s5s2D3/2→3d94 s4p2F5/2 at 464.25 nm, 4p 2P3/2→3d94s2D5/2 at 510.55 nm, 4d 2 D3/2→4p2P1/2 at 515.32 nm 4d 2 D5/2→4p2P3/2 at 521.82 nm and 4p 2 P3/2→3d94s2D3/2 at 570.02 nm transitions have been used to estimate the electron temperature through the Boltzmann plot method. The number density has been estimated from the Stark broadened profiles of the spectral lines. The spatial behaviour of the electron temperature and number density has been examined at different ambient air pressures and with laser irradiance. The temperature and number density are found to be in the range from 14700 to 13600 K and 2.1×1016 to 1.78×1016cm-3 for the 1064 nm laser, from 14200 to 12800 K and 2.2×1016 to 1.8×1016cm-3 for the 532 nm laser and from 14100 to 12500 K and 2.4×1016 to 1.9×1016cm-3 for the 355 nm laser. [ABSTRACT FROM AUTHOR]

We report the spectroscopic studies of the Kohl plasma produced in air at atmospheric pressure by Laser Induced Breakdown Spectroscopy (LIBS) and Atomic Absorption Spectroscopy (AAS) techniques. The plasma has been produce using Q-switched Nd:YAG laser at Second Harmonic Generation SHG (532 nm), with laser irradiance of 4 × 1010 W/cm2, 10 Hz repetition rate and 5ns pulse duration. From the spectroscopic analysis of the registered spectrum, we have detected the presence of Pb, C, Ca, Cr, Fe, Ba, Zn, Hg, Na and H. The electron temperature has been determined from the intensity ratio of the two transition lines of Pb– I, 368.34 nm and 373.99 nm, whereas the electron number density has been estimated from the Stark broadening profile of the H α line at 656.28 nm. It has been noticed that the maximum value of the electron temperature and electron number density at the initial stage of the plasma. The electron temperature varies as (15500–11600) K and the number density varies as (2.06 × 1017–3.62 × 1016) cm−3 with the delay time of (1-6) μs. • Laser Induced Breakdown Spectroscopy and Atomic Absorption Spectroscopy technique was used for the analysis of plasma plume • Recombination rate of kohl plasma • Kohl plasma parameters such as electron temperature, electron number density,inverse bremsstrahlung and plasma frequency. • H alpha line was used to calculate electron number density. [ABSTRACT FROM AUTHOR]