ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2015, vol. 91, 5, p. -
Study of J /ψ →ηφπ+π- at BESIII
© 2015 American Physical Society.Based on a sample of 2.25×108J/ψ events taken with the BESIII detector at the BEPCII collider, we present the results of a study of the decay J/ψ→ηφπ+π-. The Y(2175) resonance is observed in the invariant mass spectrum of φf0(980) with a statistical significance of greater than 10σ. The corresponding mass and width are determined to be M=2200±6(stat)±5(syst) MeV/c2 and Γ=104±15(stat)±15(syst) MeV, respectively, and the product branching fraction is measured to be B(J/ψ→ηY(2175),Y(2175)→φf0(980),f0(980)→π+π-)=(1.20±0.14(stat)±0.37(syst))×10-4. The results are consistent within errors with those of previous experiments. We also measure the branching fraction of J/ψ→φf1(1285) with f1(1285)→ηπ+π- and set upper limits on the branching fractions for J/ψ→φη(1405)/φX(1835)/φX(1870) with η(1405)/X(1835)/X(1870)→ηπ+π- at the 90% confidence level.