Measurement of the e+e- --> D(*)+D(*)- cross-sections

TL;DR

This paper reports the first measurements of specific e+e- to D(*)+D(*)- cross-sections at 10.58 GeV, providing new experimental data on these processes and their final state compositions.

Contribution

It presents the first measurement of e+e- to D(*)+D(*)- cross-sections and the fraction of specific final states at a given energy, using Belle detector data.

Findings

Measured cross-sections for e+e- to D*+D*- and D+D*-

Set an upper limit on e+e- to D+D- cross-section

Determined the dominant final state fraction in D*+D*- production

Abstract

In this paper we report the first measurement of $e^+e^- \to D^{(*)+}D^{(*)-}$ processes. The cross-sections for $e^+^e- \to D^{*+}D^{*-}$ and $e^+e^- \to D^+D^{*-}$ at $\sqrt{s}=10.58\mathrm{GeV}/c^2$ have been measured to be $0.65 \pm 0.04 \pm 0.07 \mathrm{pb}$ and $0.71 \pm 0.05 \pm 0.09 \mathrm{pb}$, respectively. We set an upper limit on the cross-section of e+e- --> D+ D- of $0.04 \mathrm{pb}$ at the 90% confidence level. In addition we have measured the fraction of the $D^{*\pm}_T D^{*\mp}_L$ final state in the e+e- --> D*+ D*- reaction to be $(97\pm 5)%$. The analysis is performed using $88.9 \mathrm{fb}^{-1}$ of data collected by the Belle detector at the $e^{+}e^{-}$ asymmetric collider KEKB.