title: Multimode vibrational couplings in resonant positron annihilation.
abstract: The mechanisms for multimode vibrational couplings in resonant positron annihilation are not well understood. We show that these resonances can arise from positron-induced distortions of the potential energy surface (target response to the positron field). Though these distortions can transfer energy into single- and multiquantum vibrations, they have so far been disregarded as a pathway to resonant annihilation. We also compare the existing annihilation theories and show that the currently accepted model can be cast as a special case of the Feshbach annihilation theory.
authors: Departamento de Física, Universidade Federal do Paraná, CP 19044, 81531-090 Curitiba, PR, Brazil.
authors: Sergio
authors: S
authors: d'A Sanchez
authors: Marco A P
authors: MA
authors: Lima
authors: Márcio T do N
authors: MT
authors: Varella