Diagnostics of laser-produced Mg plasma through a detailed collisional radiative model

A detailed fine-structure resolved collisional radiative model is developed to investigate the laser-produced Mg plasma. The dominant electron impact excitation and de-excitation have been considered in the model. The required electron impact excitation cross-sections for the transitions from the ground state 3s² (J=0) to the 3s3p, 3s4s, 3s3d, 3s4p, 3s5s, 3s4d, 3s5p, 3s6s, 3s5d, and 3s6p excited states and from 3s3p manifolds to other fine structure levels of 3s4s, 3s3d, 3s5s, 3s4d, 3s6s, and 3s5d configurations are calculated by relativistic distorted wave approximation theory. The plasma diagnostics is carried out by coupling the present collisional radiative model with the laser-induced breakdown spectroscopy measurements reported by Delserieys et al. [J. Appl. Phys., 106, 083304, 2009]. Five measured intense Mg-I emission line intensities viz. 383.3, 470.3, 517.8, 552.8, and 571.1 nm are used and corrected through the self-absorption to extract the plasma parameters i.e. electron temperature and electron density. The obtained plasma parameters at different delay time ranging from 100-700 ns are compared with the results of Delserieys et al. that were estimated using the Thomson scattering and Boltzmann plot approaches