Multipole decomposition of the rate of muon to electron (μ − −→ e − ) conversion in 208 Pb

CIVITARESE, O.; TARUTINA, T.

PHYSICAL REVIEW SPECIAL TOPICS. PHYSICS EDUCATION RESEARCH

AMER PHYSICAL SOC

Lugar: New York; Año: 2019 vol. 99

1554-9178

The (μ − −→ e − ) conversion in208 Pbnucleus is studied. For the elementary process we considerthe most general effective Lagrangian responsible for the lepton-flavor violation. For the nuclearstructure part, the spectrum of208 Pbis calculated by performing a diagonalization of the δ-forceinteraction in the space of particle-hole pairs, both for neutrons and protons. We calculate thecoherent contribution by direct summation of single particle excitations. The non-coherent muonto electron conversion is calculated by summing over the contributions for all possible intermediatestates in208 Pb.We perform the multipole decomposition of the transition amplitude and presentthe nuclear matrix elements of spin-dependent and spin-independent operators appearing in thetotal rate of the muon to electron conversion process. The results are presented in a way to facilitatetheir use in model-building of the electroweak process.