Fragmentation of water molecules in slow He2++H2O collisions

The fragmentation in the collision system (3)He2(+)+H2O has been investigated experimentally at projectile energies. ranging from 1 keV to 5 keV The fragments were detected at angles from 25 degrees to 130 degrees. The experimental spectra exhibit two groups of peaks. The first. one, which extends up to similar to 30 eV, is interpreted in terms of a Coulomb, explosion mechanism. A second group observed at higher energies, corresponds to fragments and scattered projectiles produced in quasi-binary,collisions. In the analysis, particular attention is paid to these energetic ions. Absolute cross sections d sigma/d Omega, differential in the observation angle, are found to be in good agreement with calculations assuming that the interaction of the screened nuclei is described by the ZBL (Ziegler, Biersack and Littmark) potential..