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【Abstract】

Quark and lepton mixing matrices contain at least 8 parameters of the Standard Model. Improving our knowledge of these parameters is a time-honored test of particle physics. In this talk, I will illustrate how recent advances in phenomenology and quantum field theory calculations pave the way to precise extractions of the Cabibbo-Kobayashi-Maskawa and Pontecorvo-Maki-Nakagawa-Sakata matrices.
The largest element of the quark mixing matrix Vud can be extracted from the precise measurements of the neutron lifetime. I will present a new top-down effective field theory approach for radiative corrections to the low-energy charged-current processes with nucleons, emphasize improvements in precision, and provide an updated extraction of the Vud matrix element.
Forthcoming neutrino oscillation experiments LBNF/DUNE (USA) and Hyper-Kamiokande (Japan) will discover or rule out charge-parity violation in the lepton sector and determine the ordering of neutrino masses. To achieve these goals, precise electron-neutrino appearance and muon-neutrino disappearance rates are compared to corresponding rates with antineutrinos. Extracting the oscillation parameters from these data requires accurate knowledge of scattering cross sections and incoming (anti)neutrino fluxes. I will present recent theoretical advances in radiative corrections, hadron structure, and QED interactions with the nuclear medium and illustrate how such theoretical inputs help to extract the lepton mixing matrix.