First Observation of the Decays chi_{cJ} -> pi^0 pi^0 pi^0 pi^0

TL;DR

This paper reports the first observation of chi_{cJ} decays into four neutral pions, measuring their branching fractions with high precision using a large dataset from BESIII.

Contribution

First observation of chi_{cJ} -> pi^0 pi^0 pi^0 pi^0 decays and precise measurement of their branching fractions.

Findings

Decay into four neutral pions observed for the first time.

Branching fractions measured with statistical and systematic uncertainties.

Results provide new insights into charmonium decay mechanisms.

Abstract

We present a study of the P-wave spin -triplet charmonium chi_{cJ} decays (J=0,1,2) into pi^0 pi^0 pi^0 pi^0. The analysis is based on 106 million \psiprime decays recorded with the BESIII detector at the BEPCII electron positron collider. The decay into the pi^0 pi^0 pi^0 pi^0 hadronic final state is observed for the first time. We measure the branching fractions B(chi_{c0} -> pi^0 pi^0 pi^0 pi^0)=(3.34 +- 0.06 +- 0.44)*10^{-3}, B(chi_{c1} -> pi^0 pi^0 pi^0 pi^0)=(0.57 +- 0.03 +- 0.08)*10^{-3}, and B(chi_{c2} -> pi^0 pi^0 pi^0 pi^0)=(1.21 +- 0.05 +- 0.16)*10^{-3}, where the uncertainties are statistical and systematical, respectively.