Observation of two new $N^*$ resonances in $\psi(3686) \rightarrow p\bar{p}\pi^0$

TL;DR

This study reports the observation of two new $N^*$ resonances in the decay of $\psi(3686)$ to $par{p}\pi^0$, based on a large dataset and partial wave analysis, expanding the understanding of nucleon excitations.

Contribution

The paper presents the first observation of two new $N^*$ resonances in $\psi(3686)$ decays, with detailed measurements of their masses and widths, using a comprehensive partial wave analysis.

Findings

Two new $N^*$ resonances observed with significant statistical evidence.

Measured masses and widths of the new resonances: 2300 MeV/$c^2$ (width 340 MeV/$c^2$) and 2570 MeV/$c^2$ (width 250 MeV/$c^2$).

Branching fraction of $\psi(3686) ightarrow par{p}\pi^0$ determined to be $(1.65 extpm0.03 extpm0.15) imes 10^{-4}$.

Abstract

Based on 106$\times10^6 \psi(3686)$ events collected with the BESIII detector at the BEPCII facility, a partial wave analysis of $\psi(3686)\rightarrow p\bar{p}\pi^0$ is performed. The branching fraction of this channel has been determined to be $B(\psi(3686)\rightarrow p\bar{p}\pi^0) = (1.65\pm0.03\pm0.15)\times 10^{-4}$. In this decay, 7 $N^*$ intermediate resonances are observed. Among these $N^*$ resonances, two new resonances are significant, one $1/2^+$ resonance with a mass of $2300^{+40}_{-30}$$^{+109}_{-0}$ $\mathrm{MeV}/c^2$ and width of $340^{+30}_{-30}$$^{+110}_{-58}$ $\mathrm{MeV}/c^2$, and one $5/2^-$ resonance with a mass of $2570^{+19}_{-10}$$^{+34}_{-10}$ $\mathrm{MeV}/c^2$ and width of $250^{+14}_{-24}$$^{+69}_{-21}$ $\mathrm{MeV}/c^2$. For the remaining 5 $N^*$ intermediate resonances, the analysis yields mass and width values which are consistent with those from established resonances.