Search for intermediate resonances and dark gauge bosons in J=ψ → γπ0η'

Date Issued
17-09-2020
Author(s)
Ablikim, M.
Achasov, M. N.
Adlarson, P.
Ahmed, S.
Albrecht, M.
Alekseev, M.
Amoroso, A.
An, F. F.
An, Q.
Bai, Y.
Bakina, O.
Ferroli, R. Baldini
Balossino, I.
Ban, Y.
Begzsuren, K.
Bennett, J. V.
Berger, N.
Bertani, M.
Bettoni, D.
Bianchi, F.
Biernat, J.
Bloms, J.
Boyko, I.
Briere, R. A.
Cai, H.
Cai, X.
Calcaterra, A.
Cao, G. F.
Cao, N.
Cetin, S. A.
Chai, J.
Chang, J. F.
Chang, W. L.
Chelkov, G.
Chen, D. Y.
Chen, G.
Chen, H. S.
Chen, J.
Chen, J. C.
Chen, M. L.
Chen, S. J.
Chen, Y. B.
Cheng, W.
Cibinetto, G.
Cossio, F.
Cui, X. F.
Dai, H. L.
Dai, J. P.
Dai, X. C.
Dbeyssi, A.
Dedovich, D.
Deng, Z. Y.
Denig, A.
Denysenko, I.
Destefanis, M.
de Mori, F.
Ding, Y.
Dong, C.
Dong, J.
Dong, L. Y.
Dong, M. Y.
Dou, Z. L.
Du, S. X.
Fan, J. Z.
Fang, J.
Fang, S. S.
Fang, Y.
Farinelli, R.
Fava, L.
Feldbauer, F.
Felici, G.
Feng, C. Q.
Fritsch, M.
Fu, C. D.
Fu, Y.
Gao, Q.
Gao, X. L.
Gao, Y.
Gao, Y. G.
Gao, Z.
Garillon, B.
Garzia, I.
Gersabeck, E. M.
Gilman, A.
Goetzen, K.
Gong, L.
Gong, W. X.
Gradl, W.
Greco, M.
Gu, L. M.
Gu, M. H.
Gu, S.
Gu, Y. T.
Guo, A. Q.
Guo, L. B.
Guo, R. P.
Guo, Y. P.
Guskov, A.
Han, S.
Hao, X. Q.
DOI
Abstract
We report on an analysis of the decay J/ψ→γπ0η′ using a sample of (1310.6±7.0)×106J/ψ events collected with the BESIII detector. We search for the CP-violating process ηc→π0η′ and a dark gauge boson U′ in J/ψ→U′η′,U′→γπ0,π0→γγ. No evidence of an ηc signal is observed in the π0η′ invariant-mass spectrum and the upper limit of the branching fraction is determined to be 5.6×10-5 at the 90% confidence level. We also find no evidence of U′ production and set upper limits at the 90% confidence level on the product branching fraction B(J/ψ→U′η′)×B(U′→π0γ) in the range between (0.8-6.5)×10-7 for 0.2≤mU′≤2.1 GeV/c2. In addition, we study the process J/ψ→ωη′ with ω→γπ0. The branching fraction of J/ψ→ωη′ is found to be (1.87±0.09±0.12)×10-4, where the first uncertainty is statistical and the second is systematic, with a precision that is improved by a factor of 1.4 over the previously published BESIII measurement.
Volume
102