Positron production in heavy-ion collisions. II. Application of the formalism to the case of the U + U collision

Abstract

The method developed in the preceding paper is applied to the calculation of the spectra of positrons produced in the U + U collision. Matrix elements of the radial derivative operator between adiabatic basis states are calculated in the monopole approximation, with the finite nuclear size taken into account. These matrix elements are then modified for the supercritical case with the use of the analytical method presented in paper I of this series. The coupled differential equations for the occupation amplitudes of the basis states are solved and the positron spectra are obtained for the U + U collision. It is shown that the decomposition of the production probability into a spontaneous and an induced part depends on the definition of the resonance state and cannot be given unambiguously. The results are compared with those obtained by Reinhardt et al.