Measurement of the branching fraction of the decay $J/\psi \to p\overline{p}\eta $

A high-precision measurement of the branching fraction of the decay $J/\psi \to p\overline{p}\eta $ is performed using $\left(10\text{}087±44\right)×{10}^{6}\text{}J/\psi $ events recorded by the BESIII detector at the BEPCII storage ring. The branching fractions of the two decays $J/\psi \to p\overline{p}\eta \left(\eta \to \gamma \gamma \right)$ and $J/\psi \to p\overline{p}\eta \left(\eta \to {\pi }^{+}{\pi }^{-}{\pi }^{0}\right)$ are measured individually to be $B\left(J/\psi \to p\overline{p}\eta \left(\eta \to \gamma \gamma \right)\right)=\left(1.480±0.001±0.024\right)×{10}^{-3}$ and $B\left(J/\psi \to p\overline{p}\eta \left(\eta \to {\pi }^{+}{\pi }^{-}{\pi }^{0}\right)\right)=\phantom{\rule{0ex}{0ex}}\left(1.557±0.003±0.038\right)×{10}^{-3}$, where the first uncertainties are statistical and the second systematic. Both results are compatible within their uncorrelated systematic uncertainties. The combined result is $B\left(J/\psi \to p\overline{p}\eta \right)=\left(1.495±0.001±0.023\right)×{10}^{-3}$, where the first uncertainty is the combined statistical uncertainty and the second one the combined systematic uncertainty of both analyses, incorporating correlations between them. In addition, the $p\overline{p}$ threshold region is investigated for a potential threshold enhancement, and no evidence for one is observed.