arXiv subjects

A. O. Davydov

Publications and source records attributed to A. O. Davydov.

3 recordsLinked to original sources

arXiv2025

Total decay rate of a muon bound to a light nucleus

We revisit the total decay rate of a muon being in the ground state of a Coulomb potential with atomic charge numbers $4\leq Z \leq 9$. The discrepancy between the perturbative $(αZ)^2$ result of [Phys. Rev. \textbf{119}, 365 (1960)] and the fully relativistic partial-wave calculation of [At. Data Nucl. Data Tables \textbf{54}, 165 (1993)] for oxygen ($Z=8$) is shown to originate from insufficient convergence of the partial-wave series in the latter work. Our accurate relativistic calculations restore agreement with the perturbative $αZ$~expansion and indicate a negative sign for the next-order $(αZ)^3$ correction.

hep-ph↗

arXiv2025

Study of atomic effects on electron spectrum in bound-muon decay process

For the bound-muon decay process, the study of atomic effects on the electron spectrum near its endpoint is performed within the framework of the Fermi effective theory. The analysis takes into account for corrections due to finite-nuclear-size, nuclear-deformation, electron-screening, and vacuum-polarization effects, all of which are incorporated self-consistently into the Dirac equation. Furthermore, the nuclear-recoil correction to the muon binding energy is included. Calculations are carried out for the isotopes of C, Al, and Si, which are of a particular importance for forthcoming experiments aimed at search for the charged-lepton flavor-violating process of muon-to-electron conversion in a nuclear field.

physics.atom-ph↗

arXiv2022

Rare radiative $Ξ^{-}_{b}\to Ξ^-γ$ decay in the relativistic quark model

Recently the LHCb collaboration put the upper limit on the $Ξ^{-}_{b} \rightarrow Ξ^{-}γ$ decay branching ratio $Br(Ξ^{-}_{b} \rightarrow Ξ^{-}γ)< 1.3\times 10^{-4}$. The measured value is below the light-cone sum rule prediction. In this paper the rare radiative decay of the $Ξ^{-}_{b}$ baryon is studied in the framework of the relativistic quark model based on the quasipotential approach and QCD. The decay form factors are calculated with the comprehensive account of the relativistic effects. The obtained result for the branching ratio is found to be below the upper limit set by LHCb and is consistent with theoretical predictions based on the SU(3) flavor-symmetry, light-front quark model and light-cone QCD sum rules in full theory within theoretical uncertainties.

hep-ph↗