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arXiv · 1311.2741

Search for isotope effects in projectile and target ionization in swift He$^+$ on H$_2$ or D$_2$ collisions

F. Trinter·M. Waitz·M. S. Schöffler·H. -K. Kim·J. Titze·O. Jagutzki·A. Czasch·L. Ph. H. Schmidt·H. Schmidt-Böcking·R. Dörner
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Abstract

Using the cold target recoil ion momentum spectroscopy (COLTRIMS) technique, we have measured the simultaneous projectile and target ionization in collisions of He$^+$ projectiles with a mixture of gaseous H$_2$ and D$_2$ for an incident projectile energy of 650 keV. Motivated by Cooper et al. [Phys. Rev. Lett. 100, 043204 (2008)], we look for differences in the ionization cross section of the two isotopes with the highest resolution and statistical significance. Contributions of the electron-electron and electron-nucleus interactions have been clearly separated kinematically by measuring the longitudinal and transverse momentum of the recoiling ion. We find no significant isotope effect in any of our momentum distributions.

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F. Trinter, M. Waitz, M. S. Schöffler, H. -K. Kim, J. Titze, O. Jagutzki, A. Czasch, L. Ph. H. Schmidt, H. Schmidt-Böcking, R. Dörner. 2014-03-06. Search for isotope effects in projectile and target ionization in swift He$^+$ on H$_2$ or D$_2$ collisions. https://doi.org/10.1103/physreva.89.032702

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