Single and double electron processes of helium targets induced by fully stripped ion impact

QUINTO M; TEREKHIN, P; MONTI, J. M.; MONTENEGRO, P; FOJÓN O A

Kielce

Conferencia; 18th International Conference on the Physics of Highly Charged Ions (HCI); 2016

Collisions between fully stripped ions and He targets are the simplest systems for investigation of multiple electron transitions. The study of these Collisional systems is crucial to fully understand the mechanisms underlying these basic reactions. Moreover, they are of interest in several fields such as heavy-ion therapy [1], thermonuclear fusion [2], hot plasmas [3], etc.In this work, multiple electron processes (single and double ionization or capture, as well as transfer-ionization) of He targets impacted by H+, He2+ and Li3+ projectiles are analyzed theoretically in detail at intermediate and high collision energies. Absolute cross sections for these processes are obtained by computation of transition probabilities as a function of the impact parameter in the framework of the Continuum Distorted Wave-Eikonal Initial State theory (CDW-EIS) [4]. A binomial analysis is employed to calculate exclusive probabilitiesusing the independent electron (IEL) model, where electron correlation is neglected [5], as well as the independent event (IEV) model, in which the ionization is viewed as a two-step process [6]. It is worthy to note that only exclusive probabilities are able to describe properly the measured cross sections taking into account all possible processes.The comparison with the available theoretical and experimental results shows that exclusive probabilities are needed for a reliable description of the experimental data. The total cross sections obtained within the IEV model and using exclusive probabilities are in better agreement with the experimental results than previous IEV calculations. The developed approach may be used to obtain the input database for modeling multiple electron processesof energetic charged particles passing through matter.References[1] U. Amaldi and G. Kraft, Rep. Prog. Phys. 68, 1861 (2005)[2] Simon S. Yu, B.G. Logan, J.J. Barnard et al., Nucl. Fusion 47, 721 (2007)[3] I. Murakami, J. Yan, H. Sato et al., At. Data Nucl. Data Tables 94, 161 (2008)[4] P.D. Fainstein, V.H. Ponce and R.D. Rivarola, Phys. B: At. Mol. Opt. Phys. 24, 3091 (1991)[5] J. Bradley, R. J. S Lee, M. McCartney and D. S. F. Crothers, J. Phys. B: At. Mol. Opt. Phys. 37, 3723 (2004)[6] D. S. F. Crothers and R. McCarroll, J. Phys. B: At. Mol. Phys. 20, 2835 (1987)