Measurement of the $e^{+}e^{-} \to K_{S}^{0} K_{L}^{0} \pi^{0}$ cross sections from $\sqrt{s}=$ 2.000 to 3.080 GeV

TL;DR

This study measures the cross sections of the process $e^{+}e^{-} o K_{S}^{0} K_{L}^{0} o ext{pions}$ in the energy range 2.000 to 3.080 GeV, revealing a potential vector meson around 2.2 GeV with improved precision.

Contribution

First precise measurement of $e^{+}e^{-} o K_{S}^{0} K_{L}^{0} o ext{pions}$ cross sections in this energy range, including subprocess analysis and evidence for a vector meson near 2.2 GeV.

Findings

Cross sections consistent with previous measurements, but more precise.

Evidence for a vector meson around 2.2 GeV with 3.2$\sigma$ significance.

Mass and width of the vector meson determined as approximately 2165 MeV/c² and 32 MeV.

Abstract

Based on $e^{+}e^{-}$ collision data collected at center-of-mass energies from 2.000 to 3.080 GeV by the BESIII detector at the BEPCII collider, a partial wave analysis is performed for the process $e^{+}e^{-}\to K_{S}^{0} K_{L}^{0} \pi^{0}$. The results allow the Born cross sections of the process $e^{+}e^{-}\to K_{S}^{0} K_{L}^{0} \pi^{0}$, as well as its subprocesses $e^{+}e^{-}\to K^{*}(892)^{0}\bar{K}^{0}$ and $K^{*}_{2}(1430)^{0}\bar{K}^{0}$ to be measured. The Born cross sections for $e^{+}e^{-}\to K_{S}^{0}K_{L}^{0}\pi^{0}$ are consistent with previous measurements by BaBar, but with substantially improved precision. The Born cross section lineshape of the process $e^{+}e^{-}\to K^{*}(892)^{0}\bar{K}^{0}$ is consistent with a vector meson state around 2.2 GeV with a significance of 3.2$\sigma$. A Breit-Wigner fit determines its mass as $M_Y=(2164.7\pm9.1\pm3.1)~{\rm{MeV}}/c^{2}$ and its width as $\Gamma_{Y}=(32.4\pm21.0\pm1.8)~\rm{MeV}$.