Study of the hc (11P1) meson via ψ (2S) →π0hc decays at BESIII

Date Issued
01-10-2022
Author(s)
Ablikim, M.
Achasov, M. N.
Adlarson, P.
Ahmed, S.
Albrecht, M.
Aliberti, R.
Amoroso, A.
An, M. R.
An, Q.
Bai, X. H.
Bai, Y.
Bakina, O.
Baldini Ferroli, R.
Balossino, I.
Ban, Y.
Batozskaya, V.
Becker, D.
Begzsuren, K.
Berger, N.
Bertani, M.
Bettoni, D.
Bianchi, F.
Bloms, J.
Bortone, A.
Boyko, I.
Briere, R. A.
Brueggemann, A.
Cai, H.
Cai, X.
Calcaterra, A.
Cao, G. F.
Cao, N.
Cetin, S. A.
Chang, J. F.
Chang, W. L.
Chelkov, G.
Chen, C.
Chen, G.
Chen, H. S.
Chen, M. L.
Chen, S. J.
Chen, T.
Chen, X. R.
Chen, X. T.
Chen, Y. B.
Chen, Z. J.
Cheng, W. S.
Cibinetto, G.
Cossio, F.
Cui, J. J.
Dai, H. L.
Dai, J. P.
Dbeyssi, A.
De Boer, R. E.
Dedovich, D.
Deng, Z. Y.
Denig, A.
Denysenko, I.
Destefanis, M.
De Mori, F.
Ding, Y.
Dong, J.
Dong, L. Y.
Dong, M. Y.
Dong, X.
Du, S. X.
Egorov, P.
Fan, Y. L.
Fang, J.
Fang, S. S.
Fang, Y.
Farinelli, R.
Fava, L.
Feldbauer, F.
Felici, G.
Feng, C. Q.
Feng, J. H.
Fischer, K.
Fritsch, M.
Fu, C. D.
Gao, Y. N.
Gao, Yang
Garzia, I.
Ge, P. T.
Geng, C.
Gersabeck, E. M.
Gilman, A.
Goetzen, K.
Gong, L.
Gong, W. X.
Gradl, W.
Greco, M.
Gu, M. H.
Guan, C. Y.
Guo, A. Q.
Guo, A. Q.
Guo, L. B.
Guo, R. P.
Guo, Y. P.
Guskov, A.
DOI
Abstract
Using 448 million ψ(2S) events, the spin-singlet P-wave charmonium state hc(1P11) is studied via the ψ(2S)→π0hc decay followed by the hc→γηc transition. The branching fractions are measured to be BInc(ψ(2S)→π0hc)×BTag(hc→γηc)=(4.22-0.26+0.27±0.19)×10-4, BInc(ψ(2S)→π0hc)=(7.32±0.34±0.41)×10-4, and BTag(hc→γηc)=(57.66-3.50+3.62±0.58)%, where the uncertainties are statistical and systematic, respectively. The hc(1P11) mass and width are determined to be M=(3525.32±0.06±0.15) MeV/c2 and Γ=(0.78-0.24+0.27±0.12) MeV. Using the center of gravity mass of the three χcJ(13PJ) mesons [M(c.o.g.)], the 1P hyperfine mass splitting is estimated to be Δhyp=M(hc)-M(c.o.g.)=(0.03±0.06±0.15) MeV/c2, which is consistent with the expectation that the 1P hyperfine splitting is zero at the lowest order.
Volume
106