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Atomic collision calculations of interest in radiobiologyJuan Manuel Monti1, Christophe Champion2 et Roberto Rivarola11. Laboratorio de Colisiones Atómicas. Instituto de Física Rosario (CONICET-UNR) and Fac. de Cs. Exactas, Ing. y Agrim., Universidad Nacional de Rosario, Rosario, Argentina2. Laboratoire de Physique Moléculaire et des Collisions, Institut de Physique de Metz, Université de Lorraine, Metz, France.monti@iﬁr-conicet.gov.arIn order to calculate with accuracy the energy deposition by ionizing radiation in an absorbing medium, theunderstanding and detailed description of the charged particle tracks is essential. It is known that radiation damagein the medium depends crucially upon the evolution of track patterns along the path of the energetic particle, andthe determination of these patterns depends on an extensive set of total and differential cross-section data for theprimary interactions of the relevant particles with the molecular constituents of the absorbing medium [1]. Thisdata must describe properly the physics involved in the reactions in order to obtain correct results when calculatingtrack patterns and energy deposition.There exists in the bibliography [2] many classical and quantum theoretical models that can be employed tocalculate the corresponding cross sections. In this work we study the extension and application of the quantumContinuum Distorted Wave (CDW, [3]) and the Continuum Distorted Wave-Eikonal Initial State (CDW-EIS, [4])models to the case of electron emission in collisions between neutral hydrogen and stripped ions (H, H+ , and C6+ )and vapor water targets, and later with biological molecules such as the DNA and RNA basis. These models whereinitially introduced to investigate the interaction between projectiles with monoelectronic targets.Working within the independent electron approximation, a ﬁrst extension made by Fainstein et al. [5] allowed toconsider targets with more than one electron. Since then they have been widely used to compute differential andtotal ionization cross sections for many systems, combining different projectiles and atomic and molecular targets,colliding at intermediate to high non-relativistic impact energies.More recently a second extension by Monti et al. [6, 7] enabled to apply these models to the case of partiallydressed projectiles.Using a CNDO (Complete Neglect of Diatomic Orbitals) description for the molecular target initial state, weuse these models to calculate ionization cross sections of water molcules by 0.5MeV H+ and 6MeV/u C6+ impact.Here we analyze the inﬂuence of the target dynamic screening [8, 9], mainly dependent on the inﬂuence of thepassive electrons over the ejected one.We also study the electron production in collisions between neutral atomic hydrogen and vapor water molecules.In this case target, projectile and simultaneous ionization can occur. Details of the theories and results will bepresented at the conference.Références[1] Champion C, L?Hoir A, Politis M F, Fainstein P D, Rivarola R D and Chetioui A 2005 Rad. Res. 163 222[2] Stolterfoht N, DuBois R and Rivarola R D 1997 Electron Emission in Heavy Ion-Atom Collisions (Berlin: Springer-Verlag)[3] Belki´ D? 1978 J. Phys. B: At. Mol. Phys. 11 3529[4] Crothers D S F and McCann J F 1983 J. Phys. B: At. Mol. Phys. 16 3229[5] Fainstein P D, Ponce V H and Rivarola R D 1988 J. Phys. B: At. Mol. Opt. Phys. 21 287[6] Monti J M, Rivarola R D and Fainstein P D 2008 J. Phys. B: At. Mol. Opt. Phys. 41 201001[7] Monti J M, Rivarola R D and Fainstein P D 2011 J. Phys. B: At. Mol. Opt. Phys. 44 195206[8] Monti J M, Fojón O A, Hanssen J and Rivarola R D 2010 Journal of Atomic, Molecular, and Optical Physics 2010 128473[9] Monti J M, Fojón O A, Hanssen J and Rivarola R D 2010 J. Phys. B: At. Mol. Opt. Phys. 43 205203