Search for the weak decay eta ' -> K-+/-pi(-/+) and precise measurement of the branching fraction B(J/psi -> phi eta ')
Citation
Ablikim, M., Achasov, M.N., Ai, X.C., Albayrak, O., Albrenht, M., Ambrose, D.J. … BESIII Collaboration. (2016). Search for the weak decay eta ' -> K-+/-pi(-/+) and precise measurement of the branching fraction B(J/psi -> phi eta '). Physical Review D, 93(7), 1-9, http://dx.doi.org/10.1103/PhysRevD.93.072008Abstract
We present the first search for the rare decay of eta' into K-+/- pi(-/+) in J/psi -> phi eta', using a sample of 1.3 x 10(9) J/psi events collected with the BESIII detector. No significant signal is observed, and the upper limit at the 90% confidence level for the ratio B(eta' -> K-+/- pi(-/+))/B(eta' -> gamma pi(+/-) pi(-/+)) is determined to be 1.3 x 10(-4). In addition, we report the measurement of the branching fraction of J/psi -> phi eta' to be [5.10 +/- 0.03(stat) +/- 0.32(syst)] x 10(-4), which agrees with previous results from BESII.
