Measurement of the Born cross sections for $e^+e^- \to \eta^\prime \pi^{+}\pi^{-}$ at center-of-mass energies between $2.00$ and $3.08$ GeV

TL;DR

This paper reports precise measurements of the cross sections for the process $e^+e^- o \\eta' \\pi^+\\pi^-$ over energies 2.00 to 3.08 GeV, revealing a resonance with parameters consistent with previous experiments.

Contribution

First precise measurement of the $e^+e^- o \\eta' \\pi^+\\pi^-$ cross section across this energy range, identifying a new resonance with detailed parameters.

Findings

Observed a resonance with mass ~2111 MeV/c^2 and width ~135 MeV.

Resonance parameters agree with previous measurements within two standard deviations.

Enhanced precision in cross section measurements over previous studies.

Abstract

The Born cross sections for the process $e^+e^- \to \eta^\prime \pi^{+}\pi^{-}$ at different center-of-mass energies between $2.00$ and $3.08$ GeV are reported with improved precision from an analysis of data samples collected with the BESIII detector operating at the BEPCII storage ring. An obvious structure is observed in the Born cross section line shape. Fit as a Breit-Wigner resonance, it has a statistical significance of $6.3\sigma$ and a mass and width of $M=(2111\pm43\pm25)$~MeV/$c^2$ and $\Gamma=(135\pm34\pm30)$~MeV, where the uncertainties are statistical and systematic, respectively. These measured resonance parameters agree with the measurements of BABAR in $e^+e^- \to \eta^\prime \pi^{+}\pi^{-}$ and BESIII in $e^+e^- \to \omega\pi^0$ within two standard deviations.