Daria M. Vasileva | Searcharxiv

arXiv2026

Hyperfine-driven polarization effects in elastic muon scattering by atomic nuclei

We present a theoretical study of polarization dynamics in the elastic scattering of muons and antimuons by high-magnetic-moment atomic nuclei, using ${}_{83}^{209}$Bi as a benchmark. The analysis tracks the evolution of (anti)muon polarization and its transfer to the nucleus, emphasizing nuclear-structure corrections. These corrections significantly alter both the differential cross sections and the polarization observables. Our results demonstrate that measuring scattered muon polarization serves as a sensitive probe for nuclear charge radii and magnetic dipole moments.

physics.atom-ph↗

arXiv2025

Electron-positron pair production in bound-bound muon transitions

We explored a distinct mechanism for matter creation via electron-positron pair production during bound-bound transitions in the deexcitation of one-muon ions. For ions with nuclear charges $Z\geq24$, transitions from low-lying excited states to the 1s-muon state can lead to the production of electron-positron pairs. We show that the Breit interaction determines the transition probabilities for states with nonzero orbital momentum. Although the $2s$ state is metastable, pair production arises mainly from the decay of the $2p$ states. Thus, the Breit interaction governs electron-positron pair production in bound-bound muon transitions. This process offers a unique opportunity to explore quantum electrodynamics in strong fields, as well as a class of nonradiative transitions involving electron-positron pair production.

physics.atom-ph↗