Quenching of para-H2 with an ultracold antihydrogen atom H̄1s

Abstract

In this work we report the results of calculation for quantum-mechanical rotational transitions in molecular hydrogen, H2, induced by an ultracold ground-state antihydrogen atom H̄1s. The calculations are accomplished using a nonreactive close-coupling quantum-mechanical approach. The H2 molecule is treated as a rigid rotor. The total elastic-scattering cross section σel(ε) at energy ε, state-resolved rotational transition cross sections σjj'(ε) between states j and j', and corresponding thermal rate coefficients kjj'(T) are computed in the temperature range 0.004 K T 4 K. Satisfactory agreement with other calculations (variational) has been obtained for σel(ε). © 2010 The American Physical Society.