Flavour physics parameters from data and unitarity

TL;DR

This paper uses current experimental decay data and unitarity constraints to accurately determine the CKM matrix, decay constants, and form factors, exemplified through D meson semileptonic decays.

Contribution

It introduces a method to extract the CKM matrix and form factors directly from data using unitarity, improving parameter determination accuracy.

Findings

Determined the most probable CKM matrix form from experimental data.

Extracted decay constants and form factors with improved precision.

Applied method successfully to D meson semileptonic decays.

Abstract

The aim of the paper is to show that the nowadays experimental data from superallowed nuclear and neutron $\beta$ decays, and from leptonic and semileptonic decays allow the finding of the most probable numerical form of the KM matrix, as well as the determination of decay constants, $f_{P}$, and of various form factors $f_+(q^2)$, by using a genuine implementation of unitarity constraints. In particular this approach allows the determination of semileptonic form factors that is illustrated on the existing data of $D\rightarrow \pi l \nu$ and $D\rightarrow K l\nu$ decays.