Foil dissociation of 40–120 keV/p hydrogen clusters

Abstract

We report on measurements of angular and charge state distributions of hydrogen fragments resulting from the dissociation of fast H + n clusters ( n ≤ 13) in a carbon foil. The proximity effects on the fragment neutralization have been investigated for beam velocities above and around the Bohr velocity. At a given velocity the angular width and the yield of neutral atoms are observed to saturate at n ≥ 5 and n ≥ 7, respectively. The interpretation of this behaviour provides some insight into the collective aspects of the collisions and into the structure of hydrogen clusters.