Determination of the $\psi(3770)$, $\psi(4040)$, $\psi(4160)$ and $\psi(4415)$ resonance parameters

TL;DR

This study analyzes BESII data to precisely determine the properties of high-mass charmonium resonances, considering various physical effects and comparing results with prior research.

Contribution

It provides updated resonance parameters for $\psi(3770)$, $\psi(4040)$, $\psi(4160)$, and $\psi(4415)$, incorporating effects like interference and radiative corrections.

Findings

Resonance masses and widths are precisely measured.

Interference effects significantly influence parameter extraction.

Results are consistent with or improve upon previous measurements.

Abstract

$R$ measurement data taken with the BESII detector at center-of-mass energies between 3.7 and 5.0 GeV is fitted to determine resonance parameters (mass, total width, electron width) of the high mass charmonium states, $\psi(3770)$, $\psi(4040)$, $\psi(4160)$ and $\psi(4415)$. Various effects, including the relative phases between the resonances, interferences, the energy-dependence of the full widths, and the initial state radiative correction, are examined. The results are compared to previous studies.