Multiple-electron losses of highly charged ions colliding with neutral atoms

Abstract

Abstract. We present calculations of the total and m-fold electron-loss cross sections using the DEPOSIT code for highly charged U q+ ions (q = 10, 31, 33) colliding with N e and Ar targets at projectile energies E = 1.4 and 3.5 MeV/u. Typical examples of the deposited energy T (b) and m-fold ionization probabilities P m (b) used for the crosssection calculations as a function of the impact parameter b are given. Calculated m-fold electron-loss cross sections are in a good agreement with available experimental data. Although the projectile charge is rather high, a contribution of multiple-electron loss cross sections to the total electron-loss cross sections is high: about 65 % for the cases mentioned.

Fast low-rank approximations of multidimensional integrals in ion-atomic collisions modelling

“…Once the analytical expansion ( 9) is obtained, the full calculation of T (b) consists of two steps (see algorithm in Section 2.2): calculation of the cross decomposition of integrand ( 16) on the extended z-mesh (26) and computation of all integrals I τ k and J τ k (b l ) for all b l from (25). There is no need in all the time recalculation of the cross approximation (28) for the full computation of these integrals.…”

Low rank approximations for the DEPOSIT computer code

“…Provided that a good low-rank approximation exists, there are very efficient cross approximation algorithms [16,20] that need only O((n + m)r) elements of a matrix to be computed. By using of our implementation of the cross approximation algorithm we decompose the energy gain ∆E(x, z) in the form (10). In Table 1 the ranks r and other numerical parameters are given for particular systems.…”

“…Theoretical development of the DEPOSIT is presented in [5,6,7,8]. Examples of calculations are reported in [9,10,11,12]. Detailed description of the code and user guide are given in [1].…”

Fast low‐rank approximations of multidimensional integrals in ion‐atomic collisions modelling

“…Theoretical development of the model is presented in [23,24,25,26]. Examples of calculations are reported in [27,28,29,30]. Detailed description of the computer code DEPOSIT and user guide are given in [31] and its updated version based on the separated representations is avialable in [32].…”