Measurement of e+e- --> D Dbar Cross Sections at the psi(3770) Resonance

TL;DR

This paper presents precise measurements of D Dbar production cross sections at the psi(3770) resonance using BESIII data, employing double-tag techniques to reduce systematic uncertainties.

Contribution

First measurement of D Dbar cross sections at psi(3770) with improved precision using double-tag method at BESIII.

Findings

Cross section for e+e- --> D0 D0bar is 3.615 nb

Cross section for e+e- --> D+D- is 2.830 nb

Systematic uncertainties are significantly reduced through the double-tag approach.

Abstract

We report new measurements of the cross sections for the production of D Dbar final states at the psi(3770) resonance. Our data sample consists of an integrated luminosity of 2.93/fb of e+e- annihilation data produced by the BEPCII collider and collected and analyzed with the BESIII detector. We exclusively reconstruct three D0 and six D+ hadronic decay modes and use the ratio of the yield of fully reconstructed D Dbar events ("double tags") to the yield of all reconstructed D or Dbar mesons ("single tags") to determine the number of D0 D0bar and D+D- events, benefiting from the cancellation of many systematic uncertainties. Combining these yields with an independent determination of the integrated luminosity of the data sample, we find the cross sections to be \sigma(e+e- --> D0 D0bar)=(3.615 +- 0.010 +- 0.038) nb and \sigma(e+e- --> D+D-)=(2.830 +- 0.011 +- 0.026) nb, where the uncertainties are statistical and systematic, respectively.