Relativistic calculation of electron impact excitation of tin: cross sections of importance in plasma modeling

Abstract

The present work includes the calculation of electron impact excitation cross sections for the fine structure resolved transitions in Sn I and Sn II, using relativistic distorted wave approximation with the aid of Dirac–Fock multiconfigurational wavefunctions. For Sn I, the cross sections are calculated for the excitations from the fine structure resolved energy levels of the manifolds, 5s25p2, 5p6s, 5p5d, and 5p6p including the ground state, 5s25p2(3P0) to the fine structure resolved levels of 5s25p2, 5p6[s, p, d, f], 5p4f, 5p5[d, f, g], and 5p7[s, p, d, f] manifolds for a wide range of projectile electron energy from 0 to 500 eV. Further, the cross sections are also calculated for the excitations of Sn II from the fine structure resolved energy levels of the manifolds, 5s25p, 5s5p2, 5s26s, 5s25d and 5s26p including the ground state, 5s25p(2P1/2) to the fine structure resolved levels of 5s5p2, 5s26[s, p, d], 5s25d, 5s27[s, p, d], and 5s28[s, p, d] manifolds. All the cross sections for Sn I except for the excitation from the ground state 5s25p2(3P0) to the fine-structure resolved excited states of 5s25p2, 5p6[s, p] and 5p5d manifolds and all the cross sections for Sn II are reported for the first time. In order to ensure the consistency of the present calculations, a comparison of the oscillator strengths and transition probabilities is carried out with the available calculations and measurements. The present cross sections are also compared with the previous calculations and observed in reasonable agreement. The calculated cross sections are of great interest in the modeling and diagnostic of various plasmas such as laser induced plasma, fusion plasma, etc. Further to ease the use of calculated cross sections, the analytic fitting of the cross sections is also provided.