- Open Access
Influence of the nuclear magnetic field on electron-positron pair production in low-energy heavy-nuclei collisions
Phys. Rev. D 112, 116016 – Published 19 December, 2025
DOI: https://doi.org/10.1103/bnrx-lhf1
Abstract
Total and energy-angle differential probabilities of positrons created in slow collisions of two identical nuclei are calculated within a relativistic two-center approach. The time-dependent Dirac equation is solved in the rotating frame using the generalized pseudospectral method in modified prolate spheroidal coordinates. The magnetic interaction induced by the motion of the nuclei is included in the Hamiltonian. The rotational coupling term is also taken into account. Angle-integrated and angle-resolved energy spectra of the emitted positrons are calculated by projecting the propagated wave function onto positive-energy plane-wave states. Our results show that the magnetic interaction leads to a slight increase in the critical internuclear distance and enhances the total positron yield by up to several percentages. However, it does not qualitatively alter the energy or angular distributions of emitted positrons. The angular distributions remain nearly isotropic. Most important, the characteristic signatures of the supercritical regime identified in the previous calculations neglecting the magnetic interaction are preserved and can help to detect spontaneous vacuum decay.
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