Multiple electron processes in Neon and Water targets colliding with proton beams

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

Kielce

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

Multiple electron processes in atomic and molecular collisions induced by ion impact are of fundamental interest in many areas such as tumor treatment [1], thermonuclear fusion [2], and plasma physics [3]. 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 impact on Ne and water targets 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) [4] 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 [5] were used to represent the atomic states of Ne. The initial wavefunctions of the active electrons bound to a particular water molecular orbital are described employing the complete neglect of the differential overlap (CNDO) approximation [6]. A trinomial distribution analysis has been employed to compute exclusive probabilities using the independent electron (IEL) model, where electron correlation is neglected [7].From the comparison with the available theoretical and experimental results, we conclude that exclusive probabilities are required for a reliable description of the processes of interest. Finally, we note that the present approach could be used as a basis for obtaining multiple electron processes cross sections for targets such as macromolecules of DNA and RNA to model scenarios for the radiobiological consequences of the impact of charged energetic particles on those macromolecules.References[1] A. Brahme, Int. J. Radiat. Oncol. Biol. Phys. 58, 603 (2004)[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] C. Clementi and C. Roetti, At. Data Nucl. Data Tables 14, 177 (1974)[6] J. Pople, D. Santry and G. Segal, J. Chem. Phys. 43, S129 (1965)[7] J. Bradley, R. J. S Lee, M. McCartney and D. S. F. Crothers, J. Phys. B: At. Mol. Opt. Phys. 37, 3723 (2004)