Contribution to Calculation of Ion Microfield Nonuniformity Effect on the Asymmetry of Lyman‐α Line in Dense Plasma

Abstract

The high orders of Stark effects on spectral line shapes are examined in the ion-static and electron-impact approximations. At first the distribution functions of the spatial derivative of the ion microfield in He + plasma are calculated for different plasma conditions when the coupling parameter is weak. We present new results about the spatial derivative ion microfield distributions and apply them to show the asymmetry of the Lyman-α(Ly-α) line in He + plasma. At the second stage we show that asymmetry is affected by the spatial derivative tensor of the local ion electric field. We have used the Monte-Carlo simulation (MCS) to compute the distribution functions for all tensor components and use them to solve the evolution equation of emitter whose solution serves to compute and therefore to show the line shape asymmetry. Good agreement of our distribution functions of ion microfield gradients and the line asymmetry with other results are obtained.

Division B Commission 14 Working Group: Collision Processes

“…Efficient algorithms for calculations of Stark-Zeeman line profiles for both static and dynamic ions are presented. Chenini et al (2011) have investigated the influence of a nonuniform microfield on the asymmetry of Ly α in a dense plasma and Difallah et al (2012) have studied the effect on its profile of an oscillating electric field. Baclawski & Musielok (2013) have presented a new approach for the evaluation of asymmetry parameters, and Galtier et al (2013) have investigated quantum mechanical interference effects in Stark broadening of intrashell transitions for dense plasma conditions.…”

“…Efficient algorithms for calculations of Stark-Zeeman line profiles for both static and dynamic ions are presented. Chenini et al (2011) have investigated the influence of a non-uniform microfield on the asymmetry of Ly α in a dense plasma and Difallah et al (2012) have studied the effect on its profile of an oscillating electric field.…”

Angular Velocity Distribution of the Electric Microfield in Plasma

“…Since Holtsmark [1] and Margenau [2], various theories have been proposed to assess the distribution function of the electric microfield W ( − → E ) [3][4][5][6][7][8][9][10]. All these works [1][2][3][4][5][6][7][8][9][10], concern the statistical properties of the microfield itself or its spatial derivatives [11][12] and serve to compute the line shapes that are useful tools to extract the information about the plasma densities and temperatures. Beside these theories, there are three others methods: MD (molecular dynamics [13]), APEX [14] and MC (Monte-Carlo [15]).…”