Ionization of water by (20-150)-keV protons: Separation of direct-ionization and electron-capture processes

F. Gobet (1) , S. Eden (1) , B. Coupier (1) , J. Tabet (1) , B. Farizon (1) , M. Farizon (1) , M.J. Gaillard (1) , M. Carré (1, 2) , S. Ouaskit (1, 3) , T.D. Märk (1, 4) , P. Scheier (1, 4)

1 IPNL - Institut de Physique Nucléaire de Lyon
2 LASIM - Laboratoire de Spectrométrie Ionique et Moléculaire
3 UH2MC - Université Hassan II [Casablanca]
4 Institut für Ionenphysik und Angewandte Physik - Institute for Ion Physics and Applied Physics [Innsbruck]

Mass analyzed product ions have been detected in coincidence with the projectile following the ionization of water by proton impact. Measurement of the projectile charge state postcollision enables the different ionization processes to be identified: direct ionization, single electron capture, and double electron capture. A complete set of partial and total absolute cross sections is reported for the direct ionization and electron capture processes initiated by proton collisions at 20–150 keV. The cross sections for the direct ionization of H2O by proton impact are compared with previous electron impact results [Straub et al., J. Chem. Phys. 108, 109 (1998)].

Domaines: Agrégats Moléculaires et Atomiques [physics.atm-clus]

F. Gobet, S. Eden, B. Coupier, J. Tabet, B. Farizon, et al.. Ionization of water by (20-150)-keV protons: Separation of direct-ionization and electron-capture processes. Physical Review A : Atomic, molecular, and optical physics [1990-2015], 2004, 70, pp.062716-1-8. ⟨10.1103/PhysRevA.70.062716⟩. ⟨in2p3-00023515⟩