Semileptonic D-decays at BESIII

TL;DR

This paper reports on detailed measurements of semileptonic D-meson decays at BESIII, including branching fractions, form factors, and phase analyses, providing new insights into charm quark transitions and hadronic effects.

Contribution

It presents the first measurements of certain decay modes, improved branching fraction determinations, and a partial wave analysis revealing S-wave contributions in D-meson semileptonic decays.

Findings

Measured branching fractions for multiple D-meson decay modes.

Performed a partial wave analysis indicating ~6% S-wave contribution.

Determined form factors and CP asymmetry in D-meson semileptonic decays.

Abstract

We present here three analyses of semileptonic $D$-meson decays based on the 2.92 fb$^{-1}$ of data collected by the BESIII experiment in 2010 and 2011 at the $\psi$(3770) peak. For the decay $D^{+}\to K^{-}\pi^{+}e^{+}\nu_{e}$, its branching fraction is measured over the whole $m_{K\pi}$ region and in the $\overline{K}^{*}(892)^{0}$ window, respectively. A partial wave analysis (PWA) is performed, indicating an \emph{S}-wave contribution of about 6\%. The \emph{S}-wave phase and the form factors are measured by the PWA and in a model-independent way. For the decay $D^{+}\to \omega e^{+}\nu_{e}$, an improved measurement of the branching fraction is performed and the form factors are determined for the first time. $D^{+}\to \phi e^{+}\nu_{e}$ is searched and an improved upper limit at 90\% confidence level is set. For the decay $D^{+}\to K_{L} e^{+}\nu_{e}$, its branching fraction is measured for the first time and the $CP$ asymmetry is presented. The product of the hadronic form factor and the CKM matrix element, $f_{+}^{K}(0)|V_{cs}|$, is also determined in this decay.