Study of the process $e^{+}e^{-}\rightarrow\phi\eta$ at center-of-mass energies between 2.00 and 3.08 GeV

TL;DR

This study measures the cross section of the process e+e- to phi eta across energies between 2.00 and 3.08 GeV, confirming previous results with higher precision and discovering a new resonant structure near 2.175 GeV.

Contribution

The paper provides the most precise measurement of the e+e- to phi eta cross section in the specified energy range and reports the observation of a new resonance at 2.175 GeV.

Findings

Consistent cross section measurements with BABAR

Observation of a resonance at 2.175 GeV

Resonance has a width of about 31 MeV

Abstract

The process $e^{+}e^{-} \rightarrow \phi\eta$ is studied at 22 center-of-mass energy points ($\sqrt{s}$) between 2.00 and 3.08 GeV using 715 pb$^{-1}$ of data collected with the BESIII detector. The measured Born cross section of $e^{+}e^{-} \rightarrow \phi\eta$ is found to be consistent with {\textsl{BABAR}} measurements, but with improved precision. A resonant structure around 2.175 GeV is observed with a significance of 6.9$\sigma$ with mass ($2163.5\pm6.2\pm3.0$) MeV/$c^{2}$ and width ($31.1_{-11.6}^{+21.1}\pm1.1$) MeV, where the first uncertainties are statistical and the second are systematic.