Partial wave analyses of $\psi(3686)\to p\bar{p}\pi^0$ and $\psi(3686)\to p\bar{p}\eta$

TL;DR

This study performs partial wave analyses of specific $\psi(3686)$ decays using a large BESIII dataset, measuring branching fractions and observing nucleon resonances to enhance understanding of decay dynamics.

Contribution

It provides the first detailed partial wave analysis of these decays, measuring branching fractions and resonance contributions with high statistical significance.

Findings

Branching fractions for $\psi(3686) o par{p}\pi^0$ and $\psi(3686) o par{p}\eta$ are measured.

Several $N^*$ states are observed in the $p\pi^0$ and $p\eta$ systems.

The ratio $\Gamma_{N(1535) o N\eta}/\Gamma_{N(1535) o N\pi}$ is determined to be approximately 1.

Abstract

Using a sample of $(2712\pm14)\times10^6$ $\psi(3686)$ events collected with the BESIII detector, we perform partial wave analyses of the decays $\psi(3686)\to p\bar{p}\pi^0$ and $\psi(3686)\to p\bar{p}\eta$. The branching fractions of $\psi(3686)\to p\bar{p}\pi^0$ and $\psi(3686)\to p\bar{p}\eta$ are determined to be $(133.9\pm11.2\pm2.3)\times10^{-6}$ or $(183.7\pm13.7\pm3.2)\times10^{-6}$ and $(61.5\pm6.5\pm1.1)\times10^{-6}$ or $(84.4\pm6.9\pm1.4)\times10^{-6}$, respectively, where the two solutions are caused by an ambiguous phase angle between resonant and continuum processes. Several well-established $N^*$ states are observed in the $p\pi^0$ and $p\eta$ systems, and the corresponding branching fractions are measured. The ratio of decay widths $\Gamma_{N(1535)\to N\eta}/\Gamma_{N(1535)\to N\pi}$ is determined to be $0.99\pm0.05\pm0.19$.