Calculation of antihydrogen formation via antiproton scattering with excited positronium

Abstract

© 2016 American Physical Society. The two-center convergent close-coupling method is used to calculate antihydrogen (H¯) formation via positronium (Ps) scattering on antiprotons (p¯) at near threshold energies. For excited Ps of energy, the 1/ behavior of the H¯ formation cross sections is valid strictly only at the respective threshold, as is the 1/ behavior for Ps in the ground state. Simple equations are given for the H¯(n=4) formation cross sections from Ps(n=3) from zero to around 0.1 eV above threshold. Some of the implications of using p¯-Ps collisions to form antihydrogen in beams, and held in traps, are discussed.