Ablikim, M.Achasov, M. N.Adlarson, PatrikAliberti, RiccardoÇetin, Serkant AliKolcu, Onur Buğra2022-12-212022-12-212022Ablikim, M., Achasov, M. N., Adlarson, P., Ahmed, S., Albrecht, M., Aliberti, R., ... & Khoukaz, A. (2022). Study of the h c (1 1 P 1) meson via ψ (2 S)→ π 0 h c decays at BESIII. Physical Review D, 106(7), 072007.http://dx.doi.org/10.1103/PhysRevD.106.072007https://hdl.handle.net/20.500.12713/3751Using 448 million psi(2S) events, the spin-singlet P-wave charmonium state h(c)(1(1)P(1)) is studied via the psi(2S) -> pi(0)h(c) decay followed by the h(c) -> gamma eta(c) transition. The branching fractions are measured to be B-Inc(psi(2S) -> pi(0)h(c)) x B-Tag (h(c) -> gamma eta(c)) = (4.22(-0.26)(+0.27) +/- 0.19) x 10(-4), B-Inc (psi(2S) -> pi(0)h(c)) = (7.32 +/- 0.34 +/- 0.41) x 10(-4) , and B-Tag (h(c) -> gamma eta(c)) = (57.66(-3.50)(+3.62) +/- 0.58)%, where the uncertainties are statistical and systematic, respectively. The h(c)(1(1)P(1)) mass and width are determined to be M = (3525.32 +/- 0.06 +/- 0.15) MeV/c(2) and Gamma = (0.78(-0.24)(+0.27)+/- 0.12) MeV. Using the center of gravity mass of the three chi(cJ) (1(3)P(J)) mesons [M(c.o.g.)], the 1P hyperfine mass splitting is estimated to be Delta(hyp) = M(h(c)) - M(c.o.g.) = (0.03 +/- 0.06 +/- 0.15) MeV/c(2), which is consistent with the expectation that the 1P hyperfine splitting is zero at the lowest order.eninfo:eu-repo/semantics/closedAccessArticle1067WOS:000892187300001Q110.1103/PhysRevD.106.072007N/A