Measurement of $e^+e^-\to pK^-\bar{\Lambda}+c.c.$ cross sections between 4.009 GeV and 4.951 GeV

TL;DR

This study measures the energy-dependent cross sections of the process $e^+e^- o pK^-ar{ ext{Lambda}} + c.c.$ across a range of energies, searches for specific excited and exotic states, and finds no evidence for their decay into this channel.

Contribution

First measurement of the cross sections for $e^+e^- o pK^-ar{ ext{Lambda}} + c.c.$ over a broad energy range, setting upper limits on certain charmonium-like states' decays.

Findings

No evidence for $ ext{psi}(4160)$, $ ext{psi}(4415)$, $ ext{psi}(4230)$, $ ext{psi}(4360)$, $ ext{psi}(4660)$ in this channel.

Upper limits on branching fractions at 90\% confidence level.

Energy-dependent cross sections measured for the first time.

Abstract

Using $e^+e^-$ collision datasets corresponding to total integrated luminosity of 21.7 fb$^{-1}$ collected with the BESIII detector at the BEPCII collider at center-of-mass energies ranging from 4.009 GeV to 4.951 GeV, the energy-dependent cross sections of $e^+e^-\to pK^-\bar{\Lambda}+c.c.$ are measured for the first time. By fitting these energy-dependent cross sections, we search for the excited $\psi$ states $\psi(4160)$ and $\psi(4415)$, and the vector charmonium-like states $\psi(4230)$, $\psi(4360)$, and $\psi(4660)$. No evidence for these is observed and the upper limits on the branching fractions of these states decaying into $pK^-\bar \Lambda+c.c.$ are set at the 90\% confidence level.