Measurement of the cross section for the associated production of the $\psi(2S)$ particle in the charm quark-antiquark pair process at 10.58 GeV in the Belle II experiment

Sumitted to PubDB: 2026-05-07

Category: Master Thesis

Tags: Run 1

Principal Authors Yu Wang
Date 2026-05-07
Belle II Number BELLE2-MTHESIS-2026-027
Abstract In electron-positron collision experiments with center-of-mass energies greater than 6 GeV, processes such as $e^+e^- \to \gamma^*/Z^0 \to c\bar{c} \to $ charmed hadrons + X can occur through the mediation of virtual photons or $Z^0$ bosons. This process is one of the simplest inclusive production processes in perturbative QCD theory, and its measurement can greatly improve our understanding of the strong interaction mechanism. This work is based on data samples collected by the Belle II detector at a center-of-mass energy of 10.58 GeV, with a total integrated luminosity of 361.65 fb$^{-1}$. The reaction cross-sections are measured in the mode $e^+e^- \to \psi(2S)$ + anything, yielding the following results: $\sigma_{e^+e^- \to \psi(2S)+\eta_c} = (30.44\pm7.69\pm1.70) {\rm fb},$ $\sigma_{e^+e^- \to \psi(2S)+\chi_{c0}} = (19.47\pm7.56\pm1.71) {\rm fb},$ $\sigma_{e^+e^- \to \psi(2S)+\eta_c(2S)} = (15.69\pm7.79\pm1.31) {\rm fb},$ $\sigma_{e^+e^- \to \psi(2S)+X(3940)} = (14.16\pm9.87\pm0.79) {\rm fb},$ $\sigma_{e^+e^- \to \psi(2S)+D^0\bar{D}^0} = (116.20\pm 60.48\pm10.18) {\rm fb},$ $\sigma_{e^+e^- \to \psi(2S)+D^+D^-} = (558.69\pm137.88\pm46.76) {\rm fb},$ and $\sigma_{e^+e^- \to \psi(2S)+D^{*+}D^-} = (283.60\pm111.50\pm23.74) {\rm fb}.$ The first value represents the measured central cross-section, the second value is the statistical uncertainty, and the third value is the systematic uncertainty.
Institute Nankai

Files