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We present optical emission studies of the laser ablation brass plasma generated by the fundamental, second, and third harmonics of a neodymium doped yttrium aluminum garnet laser. The spectra predominantly reveal the spectral lines of the neutral and singly ionized copper and zinc. The excitation temperatures are determined by the Boltzmann plot method, whereas the electron number densities have been extracted from the Stark broadened line profiles. The spatial variations in the spectral line intensities and the plasma parameters at 1000, 500, and 100 mbar air pressures have been evaluated. Besides, the effect of the ambient gases (He, Ne, and Ar), the laser irradiance, and the laser wavelengths on the plasma parameters have been investigated. [ABSTRACT FROM AUTHOR]

Optical emission spectroscopy is used to characterize the laser-produced strontium plasma by using the fundamental, second, and third harmonics of a Nd:YAG laser. Variations in the electron temperature (Te) and number density (Ne) as a function of distance, laser irradiance, and ambient gas pressure have been studied by using the emission lines of neutral strontium. In addition, absorption mechanisms responsible for the variation of the electron temperature and number density and the dependence of the spectral line intensities on the ambient gas pressure and laser irradiance are discussed. [ABSTRACT FROM AUTHOR]

Abstract: We report the measurement of the zinc and cadmium plasma parameters produced by the fundamental, second, and third harmonics of the neodymium-doped yttrium aluminium garnet laser. The excitation temperature has been determined from the Boltzmann plot method, whereas the electron number density is estimated from the Stark broadened profile of several spectral lines. The temporal evolution of the plasma has also been investigated. Besides, we present experimental relative transition probabilities of the Zn (4s5s 3S1 →4s4p 3P0,1,2) and Cd (5s6s 3S1 →5s5p 3P0,1,2) triplets and compare our data with that listed in the National Institute of Standards and Technology database. The experiments have been performed in air but also in He, Ne and Ar atmosphere to study the effects of ambient gas environment on the emission intensity of the atomic and ionic lines and on the plasma parameters. [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]