Antiproton capture by simple atoms and molecules

Abstract

Antiprotonic atoms form in low-energy collisions between an antiproton and a normal atom or molecule. The fermion molecular dynamics (FMD) method enables us to go beyond the atomic hydrogen target and study multielectron effects with helium and neon targets and molecular effects with hydrogen and deuterium targets. Multiple ionization and ro-vibrational excitation are found to greatly increase the maximum energy of capture, with the latter leading to a significant dependence on the projectile mass and target isotope. The kinetic energies of the ionized electrons are found to increase somewhat with the target nuclear charge.