Measured Stark Widths of Several Sniand SniiSpectral Lines in a Laser‐induced Plasma

Abstract

Data on Stark widths of spectral lines are of high interest for astrophysics and analytical techniques of stellar plasma diagnosis. Stark widths of 43 spectral lines of Sn i and 27 spectral lines of Sn ii has been measured in a laser-induced plasma ( LIP) at an electron temperature of 11,000 K and an electron density of 1:1 ; 10 16 cm À3 . The LIP optical emission spectroscopy generated by a 10640 8 radiation, with a flux of 1:4 ; 10 10 W cm À2 on several tin and lead targets in an atmosphere of argon was recorded at 2.5 s and analyzed between 1890 and 7000 8. The population level distribution and the corresponding temperatures were obtained using Boltzmann plots. The plasma electron densities were determined using well-known Stark broadening parameters of spectral lines. Special attention was dedicated to the possible self-absorption of the different transitions. The local thermodynamic equilibrium (LTE) conditions and plasma homogeneity have been checked. The experimental results obtained have been compared with the experimental and theoretical values given by other authors. The results obtained in this study will allow a substantial improvement in the interpretation of the data of the ultraviolet spectrum of the tin observed by the Goddard High Resolution Spectrograph aboard the Hubble Space Telescope. These atomic data are relevant to the analysis of the isotopic abundances of tin in stellar atmospheres.

Spectroscopic analysis of temperature and density of Sn plasma produced by a CO2 laser

“…One possible explanation of the lower temperature in the region far away from the target surface is the smaller interaction region in CO 2 laser with Sn 0.00 1.50x10 16 3.00x10 16 4.50x10 16 6.00x10 16 Electron density (cm -3 ) FIG. The estimated value of the temperature and electron number density in the present work of the CO 2 laser are much lower than the reported work of the 1.064 m Nd:YAG laser.…”

Measurement of plasma electron density generated in an experiment of Laser Shock Processing, utilizing the Hα-line

“…LIBS is based on the spectroscopic study of the emission of the present species in the plasma, and the advantage consists of obtaining its parameters and has been used by these authors in several works. Before, we have obtained temperature, electron density, atomic parameters and Stark broadening parameters in different laser induced plasma as: several parameter in aluminum plasma (Colon et al, 1993); transition probabilities of Pb III in lead plasma (Colon et al, 1999); Stark widths of spectral lines of Pb II in lead plasma (Colon and Alonso-Medina, 2006); transition probabilities of Pb Sn II in tin plasma (Alonso-Medina et al, 2003); Stark widths of several Pb III spectral lines in lead plasma (Alonso-Medina and Colon, 2007); Stark widths of several Sn I and Sn II spectral lines in tin plasma (Alonso-Medina and Colon, 2008); transition probabilities of Sn I in tin-lead plasma (Alonso-Medina, 2010) and recently the transition probabilities of Ca I in calcium-lead plasma (Alonso-Medina, 2014).…”

Collimation of laser-produced plasmas using axial magnetic field

“…The ion broadening parameters G is typically negligible for nonhydrogenic ions compared with electron contribution and can be neglected. The spectroscopic parameters are obtained from NIST data base and Alonso- Medina and Colon (2008). The density has been estimated from the time integrated line intensities with the duration of 2000 ns.…”