32 research outputs found
First observation of the decays χcJ→π0π0π0π0
We present a study of the P-wave spin-triplet charmonium χ cJ decays (J=0, 1, 2) into π0π0π0π0. The analysis is based on 106×106 ψ⊃′ decays recorded with the BESIII detector at the BEPCII electron positron collider. The decay into the π0π0π0π0 hadronic final state is observed for the first time. We measure the branching fractions B(χ c0→π0π0π0π0)=(3.34±0. 06±0.44)×10⊃-3, B(χ c1→π0π0π0π0) =(0.57±0.03±0.08)×10⊃-3, and B(χ c2→π0π0π0π0)=(1.21±0.05±0.16) ×10⊃-3, where the uncertainties are statistical and systematical, respectively. © 2011 American Physical Society.published_or_final_versio
Measurement of the matrix element for the decay η′→ηπ +π -
The Dalitz plot of η⊃′→ηπ⊃+π⊃- decay is studied using (225.2±2.8)×106 J/ψ events collected with the BESIII detector at the BEPCII e⊃+e⊃- collider. With the largest sample of η⊃′ decays to date, the parameters of the Dalitz plot are determined in a generalized and a linear representation. Also, the branching fraction of J/ψ→γη⊃′ is determined to be (4.84±0.03±0.24)×10⊃-3, where the first error is statistical and the second systematic. © 2011 American Physical Society.published_or_final_versio
Study of a00(980)-f0(980) mixing
Using samples of 2.25×108 J/ψ events and 1.06×108 ψ ′ events collected with the BES III detector, we study the f 0(980)→a00(980) and a00(980)→f 0(980) transitions in the processes J/ψ→φf 0(980) →φa00(980) and χ c1→π0a00(980)→π0f 0(980), respectively. Evidence for f 0(980)→a00(980) is found with a significance of 3.4σ, while in the case of a00(980)→f 0(980) transition, the significance is 1.9σ. Measurements and upper limits of both branching ratios and mixing intensities are determined. © 2011 American Physical Society.published_or_final_versio
Evidence for psi' decays into gamma pi^0 and gamma eta
The decays psi'->gamma pi^0, gamma eta and gamma eta' are studied using data
collected with the BESIII detector at the BEPCII e^+e^- collider. Processes
psi'->gamma pi^0 and psi'->gamma eta are observed for the first time with
signal significances of 4.6 sigma and 4.3 sigma, respectively. The branching
fractions are determined to be: B(psi'->gamma pi^0)=(1.58+-0.40+-0.13)x10^{-6},
B(psi'->gamma eta)=(1.38+-0.48+-0.09)x10^{-6}, and B(psi'->gamma
eta')=(126+-3+-8) x 10^{-6}, where the first errors are statistical and the
second ones systematic.Comment: 6 pages, 4 figure
Observation of \chi_{cJ} decaying into the p\bar{p}K^{+}K^{-} final state
First measurements of the decays of the three states to
final states are presented. Intermediate and resonance states are observed, and
branching fractions for ,
, and are reported. We also
measure branching fractions for direct
decays. These are first observations of decays to unstable baryon
resonances and provide useful information about the states. The
experiment uses samples of mesons produced via radiative
transitions from 106 million mesons collected in the BESIII
detector at the BEPCII collider.Comment: 16 pages, 5 figure