Measurements of D and Ds decay constants at CLEO

TL;DR

This paper reports measurements of the decay constants fD and fDs for D and Ds mesons using CLEO data, providing experimental results that compare with theoretical lattice QCD calculations and discussing their implications.

Contribution

First experimental determination of fD and fDs decay constants at CLEO with radiative corrections, comparing results to lattice QCD predictions and analyzing their implications.

Findings

Measured fD = (205.8 +- 8.5 +- 2.5) MeV

Measured fDs = (267.9 +- 8.2 +- 3.9) MeV

Results agree with lattice QCD for D+ but not for Ds

Abstract

Using CLEO data collected at 3370 MeV and 4170 MeV, we determine fD = (205.8 +- 8.5 +- 2.5) MeV and an interim preliminary value of fDs = (267.9 +- 8.2 +- 3.9) MeV, where both results are radiatively corrected. They agree with the recent most precise unquenched Lattice-QCD calculation for the D+, but do not for the Ds. Several consequences are discussed.