Abstract
The decay of J/psi to three photons is studied using psi (3686) -> pi(+) pi(-) J/psi in a sample of 1.0641 X 10(8) psi (3686) events collected with the BESIII detector. Evidence of the direct decay of eta(c) to two photons, eta(c) -> gamma gamma, is reported, and the product branching fraction is determined to be B(J/psi -> gamma eta(c,) eta(c) -> gamma gamma = (4.5 +/- 1.2 +/- 0.6) X 10(-6), where the first error is statistical and the second is systematic. The branching fraction for J/psi -> 3 gamma is measured to be (11.3 +/- 1.8 +/- 2.0) X 10(-6) with improved precision. DOI: 10.1103/PhysRevD.87.032003
Original language | English |
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Article number | 032003 |
Number of pages | 7 |
Journal | Physical Review D |
Volume | 87 |
Issue number | 3 |
DOIs | |
Publication status | Published - 8-Feb-2013 |
Keywords
- DECAY-RATE
- POSITRONIUM
- CHARMONIUM
- PRECISION
- BESIII