Measurement of Born cross sections of $e^+e^-\to\Xi^0\bar{\Xi}^0$ and search for charmonium(-like) states at $\sqrt{s}$ = 3.51-4.95 GeV

TL;DR

This study measures the cross sections of $e^+e^- o ext{Xi}^0ar{ ext{Xi}}^0$ over a range of energies, searches for charmonium-like states, and tests theoretical models with no significant new states found.

Contribution

First comprehensive measurement of $e^+e^- o ext{Xi}^0ar{ ext{Xi}}^0$ cross sections across 3.51-4.95 GeV, including limits on charmonium-like state decays and isospin symmetry tests.

Findings

No significant charmonium(-like) signals observed.

Upper limits set on decay branching fractions.

Cross section ratios consistent with isospin symmetry.

Abstract

Using $e^+e^-$ collision data collected by the BESIII detector at BEPCII corresponding to an integrated luminosity of 30 $\rm fb^{-1}$, we measure Born cross sections and effective form factors for the process $e^+e^-\to\Xi^0\bar{\Xi}^0$ at forty-five center-of-mass energies between 3.51 and 4.95 GeV. The dressed cross section is fitted, assuming a power-law function plus a charmonium(-like) state, i.e., $\psi(3770)$, $\psi(4040)$, $\psi(4160)$, $\psi(4230)$, $\psi(4360)$, $\psi(4415)$ or $\psi(4660)$. No significant charmonium(-like) state decaying into $\Xi^0\bar\Xi^0$ is observed. Upper limits at the 90% confidence level on the product of the branching fraction and the electronic partial width are provided for each decay. In addition, ratios of the Born cross sections and the effective form factors for $e^+e^-\to\Xi^0\bar{\Xi}^0$ and $e^+e^-\to\Xi^-\bar{\Xi}^+$ are also presented to test isospin symmetry and the vector meson dominance model.