Binary theory of antiproton stopping

Abstract:

Binary theory of electronic stopping, developed recently with the aim of quantifying stopping forces on swift heavy ions, has been applied to antiproton stopping. Essential ingredients in the theory are inverse-Bloch and shell corrections. The numerical input consists of the excitation spectrum of the stopping material, characterized by bundled oscillator strengths extracted from tabulated optical properties. Predicted stopping forces for eight solid materials agree well with experimental data, in particular for Si where measurements span over two decades of projectile energy. Large discrepancies were found with stopping data for helium extracted from annihilation time measurements.