Neonization method to calculate multiple ionization cross sections of water molecules by ion impact

M.E. GALASSI; V. TESSARO; BEUVE, M.; B. GERVAIS

Cluj- Napoca

Simposio; 27 TH INTERNATIONAL SYMPOSIUM ON ION‑ATOM COLLISIONS; 2021

Faculty of Physics, Babeș-Bolyai University

Neonization method to calculate multiple ionization cross sections of water molecules by ion impact Mariel E Galassi1, Verónica B. Tessaro1,2, Benoit Gervais3 and Michael Beuve21Grupo de Física Biomédica, Instituto de Física de Rosario (CONICET-UNR) and Facultad de Ciencias Exactas, Ingeniería y Agrimensura, Universidad Nacional de Rosario, Argentina. 2Université de Lyon 1, CNRS/IN2P3, Institut de Physique des 2 Infinis de Lyon, France. 3Centre de Recherche sur les Ions, les Matériaux et la Photonique, CIMAP-CIRIL-Ganil, CEA/CNRS/ENSICAEN/Université de Caen-Basse Normandie UCBN, Francegalassi@fceia.unr.edu.arIn the present work, multiple ionization cross sections of water molecules by proton and light ion impact are calculated in the framework of the Independent Electron Model (IEM). To keep the model as simple as possible, the impact parameter single-particle ionization probabilities, required by the IEM, are described by means of decreasing exponential functions. The parameters of these functions are obtained from total net ionization cross sections for each molecular orbital, calculated by applying the Continuum Distorted Wave-Eikonal Initial State approximation [1]. The contribution of Auger and Coster-Kronig electron emission to multiple ionization cross sections is included by using the Ne post-collisional emission probabilities [2], considering that H2O and Ne are isoelectronic. This post-collisional treatment offers a simple alternative to the much more complex evaluation of the molecular post-collisional relaxation. The results are in close agreement with experimental data for proton and other light ions, as shown in Figure 1. References[1] B. Gervais, M. Beuve, G. Olivera, M. Galassi. Numerical simulation of multiple ionization and high LET effects in liquid water radiolysis. Radiation Physics and Chemistry 75(4), (2006) 493?513[2] M. Galassi, R. Rivarola, P. Fainstein. Multiple electron emission from noble gases colliding with proton beams, including postcollisional effects. Physical Review A - Atomic, Molecular, and Optical Physics 75(5), (2007), 1?7.