Leptonic D and D_s Decays near c-cbar Threshold

TL;DR

This paper reports precise measurements of leptonic decay rates of D and D_s mesons near the charm-anticharm threshold, leading to updated decay constants and their ratio, which are crucial for understanding heavy meson decay dynamics.

Contribution

The study provides new experimental values for decay constants of D and D_s mesons near threshold, improving the precision of these fundamental parameters.

Findings

Decay constant f_D = 222.6 MeV with uncertainties

Decay constant f_Ds = 274 MeV with uncertainties

Ratio f_Ds/f_D = 1.23 with uncertainties

Abstract

We present recent results from the CLEO Collaboration on leptonic decay rates of $D$ and $D_s$ near $c\bar{c}$ production threshold. From these decay rates, we extract the decay constants, f_D = (222.6+-16.7^{+2.8}_{-3.4}) MeV, f_Ds = (274+-10+-5) MeV, and the ratio f_Ds/f_D = 1.23+-0.11+-0.03.