onization, Capture and Transfer-Ionization Processes of Ar Targets by Proton and Antiproton Impact.

M.A. QUINTO; R. D. RIVAROLA; J.M. MONTI; P.N. TEREKHIN; O.A. FOJÓN

Lisbon

Conferencia; 19th International Conference Physics of Highly Charged Ions; 2018

Multiple ionization, capture and transfer-ionization processes of the heaviest rare gases induced by ion impact are of fundamental interest in many areas such as thermonuclear fusion [1], and plasma physics [2]. A particular charge state of the residual target may be produced by the combination of single electron reactions. Therefore, it is important to understand each of them to elucidate the basic governing mechanisms in multiple electron processes.Proton and antiproton impact on Ar atoms are chosen in this work to investigate theoretically multiple-electron processes at intermediate and high collision energies. The Continuum Distorted Wave-Eikonal Initial State approximation (CDW-EIS) [3] is used to calculate transition probabilities (capture and ionization) as a function of the impact parameter and absolute cross sections for the considered collisions. The Roothaan?Hartree?Fock (RHF) wavefunctions [4] were used to represent the atomic states of Ar. A trinomial distribution analysis has been employed to compute multiple-electron probabilities using the independent electron (IEL) model, where electron correlation is neglected [5]. Influence of the post-collisional ionization (Auger processes) on absolute cross sections of the studied reactions has been investigated for different sets of experimental photoionization branching ratios.The results are compared with other theoretical calculations and recent measurements. The developed approach may be used to obtain the input database for modeling multiple electron processes of energetic charged particles passing through matter.