Study of D0 --> pi- e+ nu(e), D+ --> pi0 e+ nu(e), D0 --> K- e+ nu(e), and D+ --> anti-K0 e+ nu(e) in Tagged Decays of the psi(3770) Resonance

TL;DR

This paper measures semileptonic D meson decay rates using psi(3770) data, compares results with Lattice QCD predictions, and extracts CKM matrix elements |Vcd| and |Vcs| with quantified uncertainties.

Contribution

It provides precise measurements of D meson semileptonic decay rates and tests LQCD form factor calculations, improving the determination of CKM matrix elements.

Findings

Measured branching fractions for four D meson decay modes.

Extracted |Vcd| and |Vcs| with detailed uncertainty analysis.

Validated LQCD form factor predictions against experimental data.

Abstract

Using psi(3770) --> DDbar events collected with the CLEO-c detector at the Cornell e+ e- storage ring, tagged by fully reconstructing one D meson in a hadronic decay mode, we measure absolute branching fractions and differential decay rates for D0 --> pi- e+ nu(e), D+ --> pi0 e+ nu(e), D0 --> K- e+ nu(e), and D+ --> anti-K0 e+ nu(e). The measured decay rates are used to study semileptonic form factors governing these transitions and to test unquenched Lattice QCD (LQCD) calculations. We average our results with previously published CLEO-c measurements of the same quantities using a neutrino reconstruction technique. Combining LQCD calculations of form factor absolute normalizations f+(0) and measurements of f(pi)+(0)*|Vcd| and f(K)+(0)*|Vcs|, we find |Vcd| = 0.223(8)(3)(23) and |Vcs| = 1.019(10)(7)(106), where the uncertainties are statistical, experimental systematic, and from LQCD, respectively.