Consistent QED approach to calculation of electron‐collision excitation cross sections and strengths: Ne‐like ions

Abstract

ABSTRACT:We present the uniform energy approach, formally based on the quantum electrodynamics, using the gauge invariant scheme of generation of the optimal one-electron representation, for the calculation of electron-collision strengths and cross sections. The aim is to study, in a uniform manner, elementary processes responsible for emission-line formation in plasmas. The electron-collision excitation cross sections and strengths for some Ne-like ions (Fe, Ba) are calculated. To test the results of calculations, we compare them with the calculations of other investigators and with the available experimental data.

SENSING THE OPTIMAL PLASMA PARAMETERS FOR X-RAY LASING: CALCULATION OF ELECTRON-COLLISION STRENGTHS FOR Ar-LIKE PLASMA

“…The key momet of present calculation is the using the Debye shielding approximation. It is a main difference from the analogous calculation for Ne-like [11][12][13] and Ar-like [17] ions. Recent advances in ultra-short laser technologies have shown laser plasmas tyo be a favourable source of quantum emission.…”

“…The properties of laser-produced hot and dense plasmas, known as laser plasma, have drawn considerable attention ove the last two decades through the recent laser-fusion studies [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. Similar interest is also stimulated by importance of this information for correct determination of the characteristics for plasma in thermonuclear (tokamak) reactors, searching new mediums for X-ray range lasers.…”

“…In ref. [10][11][12][13][14] two new consistent relativistic and QED versions for calculations of the spectroscopic characteristics of the multicharged ions in plasma have been developed. Ih this paper we use them for sensing and diagnostics of the laser plasma parameters, i.e.…”

“…Let us present the key moments of the new consistent perturbation theory (PT) version for calculation of the electron collision strengths and rate coefficients of electron-collisional excitation for ions in a plasma [12][13][14]. It bases on the gauge invariant QED energy approach to construsction of the relativictic functions basis s [15,16] and using the Green s function method for accounting of the complex exchange-correlation, radiation and others corrections.…”

“…Here Qul Q λ , Br Q λ are corresponding to the Coulomb and Breit inter-electron interaction, which expresses through the radial integrals of the Coulomb (Yukawa) inter-electron interaction [11,13]. To calculate all necessary matrix elements one must use the basis s of the 1QP relativistic functions.…”