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

Abstract

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 the 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, 5 s 2 5 p 2 , 5 p 6 s , 5 p 5 d , and 5 p 6 p including the ground state, 5 s 2 5 p 2 ( 3 P 0 ) to the fine structure resolved levels of 5 s 2 5 p 2 , 5 p 6 [ s , p , d , f ] , 5 p 4 f , 5 p 5 [ d , f , g ] , and 5 p 7 [ 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, 5 s 2 5 p , 5 s 5 p 2 , 5 s 2 6 s , 5 s 2 5 d and 5 s 2 6 p including the ground state, 5 s 2 5 p ( 2 P 1 / 2 ) to the fine structure resolved levels of 5 s 5 p 2 , 5 s 2 6 [ s , p , d ] , 5 s 2 5 d , 5 s 2 7 [ s , p , d ] , and 5 s 2 8 [ s , p , d ] manifolds. All the cross sections for Sn I except for the excitation from the ground state 5 s 2 5 p 2 ( 3 P 0 ) to the fine-structure resolved excited states of 5 s 2 5 p 2 , 5 p 6 [ s , p ] and 5 p 5 d 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 previous calculations and observed to be 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.