Production and Decay of Charmed Mesons in the Upsilon Energy Region

TL;DR

This study investigates the production, decay, and hadronization of charmed mesons in electron-positron collisions near the Upsilon resonances, providing detailed measurements and comparisons with theoretical models.

Contribution

It presents new measurements of charmed meson production rates, decay modes, and fragmentation distributions in the Upsilon energy region, and compares them with existing models.

Findings

Measured D meson production cross sections and decay mode probabilities.

Analyzed fragmentation distributions and compared with theoretical models.

Identified potential effects of final state interactions and non-spectator effects.

Abstract

We study the properties of charmed, nonstrange, $\rm D$ mesons produced in continuum $\rm {e^+}{e^-}$ annihilations. The $ \rm {e^+}{e^-}$ collisions were generated in the energy region of the $ \rm \Upsilon(3S)$ and $ \rm \Upsilon(4S)$ resonances by the Cornell Electron Storage Ring, and were analyzed by the CLEO detector. We make extensive study of the decay topology $\rm D^0, D^+ \rightarrow \overline{{\rm K}}^{_{_0}}X$, where the $\overline{{\rm K}}^{_{_0}}$ is observed in the final state $\rm K^{0}_{S} \rightarrow \pi^+\pi^-$. The decay $ \rm D^+ \rightarrow K^- \pi^+\pi^-$ is also considered. We analyze the hadronization process through which charmed quarks become charmed hadrons. We measure the probability that a charmed meson will be produced in a state of non zero angular momentum. A comparison of the $\rm D^0$ and $\rm D^+$ fragmentation distributions is made to different fragmentation models, and to other charmed hadrons. A measurement of the relative production of several $\rm D^+$ decay modes is made, and the total $\rm D^0$ and $\rm D^+$ cross sections are estimated. Techniques are presented for the analysis of satellite mass peaks and $\rm D^+ \Leftrightarrow D^{+}_{s}$ reflections. We search for nonspectator effects in the weak decays of charmed mesons, and for evidence of hadronic final state interactions in $\rm D^0$ decay.