Measurement of $Σ^+$ transverse polarization in $e^+e^-$ collisions at $\sqrt{s} = 3.68-3.71$ GeV

Abstract: Using $e^+e^-$ collision data collected with the BESIII detector at seven energy points ranging from 3.68 to 3.71 GeV and corresponding to an integrated luminosity of $652.1~{\rm pb^{-1}}$, we present an energy-dependent measurement of the transverse polarization, relative phase and modulus ratio of the electromagnetic form factors of the $\Sigma^+$ hyperon in the $e^+e^- \to \Sigma^+ \bar{\Sigma}^-$ reaction. These results are helpful to understand the production mechanism of the $\Sigma^+$-$\bar\Sigma^-$ pairs.