Ablikim, M.Achasov, M. N.Adlarson, P.Ahmed, S.Albrecht, M.Aliberti, R.Çetin, Serkant AliKolcu, Onur Buğra2021-12-212021-12-212021Ablikim, M., Achasov, M. N., Adlarson, P., Ahmed, S., Albrecht, M., Aliberti, R., ... & Kolcu, O. B. (2021). Measurement of the absolute branching fractions of J/ψ→ γ η and η decay modes. Physical Review D, 104(9), 092004.2470-00102470-0029https://doi.org/10.1103/PhysRevD.104.092004https://hdl.handle.net/20.500.12713/2333Based on a data sample of (1.0087 +/- 0.0044) x 10(10) J/psi events collected by the BESIII detector at the BEPCII accelerator, the absolute branching fraction (BF) of the decay J/psi -> gamma eta is measured with high precision using events in which the radiative photon converts to e(+)e(-). Using the measured absolute BF of J/psi -> gamma eta, the absolute BFs of four dominant. decay modes are measured for the first time. The results are B(J/psi -> gamma eta) = (1.067 +/- 0.005 +/- 0.023) x 10(-3), B(eta ->gamma gamma) = (39.86 +/- 0.04 +/- 0.99)%, B(eta ->pi(0)pi(0)pi(0)) = (31.96 +/- 0.07 +/- 0.84)%, B(eta -> pi(+)pi(-)pi(0)) = (23.04 +/- 0.03 +/- 0.54)%, and B(eta -> pi(+)pi(-)gamma) = (4.38 +/- 0.02 +/- 0.10)%, where the first and second uncertainties are statistical and systematic, respectively. The results are consistent with the world average values within two standard deviations.eninfo:eu-repo/semantics/openAccessArticle1049WOS:0007225349000102-s2.0-85121056312Q110.1103/PhysRevD.104.092004Q1