Electron capture from pair creation in relativistic heavy-ion collisions as a charge transfer process

Abstract

The production of bound-free electron-positron pairs in relativistic heavy-ion collisions is investigated within a perturbative two-center description. We consider this process as the transfer of a negative-energy electron in the Coulomb field of the target nucleus to a bound state of the projectile. Cross sections are calculated by employing the Oppenheimer-Brinkman-Kramers (OBK) approximation incorporating exact Coulomb-Dirac wave functions. We show that this transfer-like reaction competes in magnitude with the usual excitation-type process, demonstrating that distortions due to both Coulomb centers are important in the 1 GeV/u energy range.