Measurements of h_{c}(^{1}P_{1}) in ψ^{′} Decays

Physical Review D, 2011

We present a study of the P-wave spin-triplet charmonium χcJ decays (J=0, 1, 2) into π0π0π0π0. The analysis is based on 106×106 ψ' decays recorded with the BESIII detector at the BEPCII electron positron collider. The decay into the π0π0π0π0 hadronic final state is observed for the first time. We measure the branching fractions B(χc0→π0π0π0π0)=(3.34±0.06±0.44)×10-3, B(χc1→π0π0π0π0)=(0.57±0.03±0.08)×10-3, and B(χc2→π0π0π0π0)=(1.21±0.05±0.16)×10-3, where the uncertainties are statistical and systematical, respectively.

The European Physical Journal C, 2017

Using decays to φ-meson pairs, the inclusive production of charmonium states in b-hadron decays is studied with pp collision data corresponding to an integrated luminosity of 3.0 fb -1 , collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. Denoting by Here and below the first uncertainties are statistical and the second systematic. Upper limits at 90% confidence level for the inclusive production of X (3872), X (3915) and χ c2 (2P) states are obtained as R X (3872) χ c1 < 0.34, R X (3915) χ c0 < 0.12 and R χ c2 (2P) χ c2 < 0.16. Differential cross-sections as a function of transverse momentum are measured for the η c (1S) and χ c states. The branching fraction of the decay B 0 s → φφφ is measured for the first time, B(B 0 s → φφφ) = (2.15 ± 0.54 ± 0.28±0.21 B )×10 -6 . Here the third uncertainty is due to the branching fraction of the decay B 0 s → φφ, which is used for normalization. No evidence for intermediate resonances is seen. A preferentially transverse φ polarization is observed. The measurements allow the determination of the ratio of the branching fractions for the η c (1S) decays to φφ and p p as B(η c (1S) → φφ)/B(η c (1S) → p p) = 1.79 ± 0.14 ± 0.32.

Physical Review Letters, 2010

Physical Review D, 2002

We report branching fraction measurements for exclusive decays of charged and neutral B mesons into two-body final states containing a charmonium meson. We use a sample of 22.72 +/- 0.36 million B anti-B events collected between October 1999 and October 2000 with the BABAR detector at the PEP-II storage rings at the Stanford Linear Accelerator Center. The charmonium mesons considered here are J/psi, psi(2S), and chi_c1, and the light meson in the decay is either a K, K^*, or pi^0.

Physical Review D, 2014

Using data samples of 102 × 10 6 Υ(1S) and 158 × 10 6 Υ(2S) events collected with the Belle detector, a first experimental search has been made for double-charmonium production in the exclusive decays Υ(1S, 2S) → J/ψ(ψ ′) + X, where X = η c , χ cJ (J = 0, 1, 2), η c (2S), X(3940), and X(4160). No significant signal is observed in the spectra of the mass recoiling against the reconstructed J/ψ or ψ ′ except for the evidence of χ c1 production with a significance of 4.6σ for Υ(1S) → J/ψ + χ c1. The measured branching fraction B(Υ(1S) → J/ψ + χ c1) is (3.90 ± 1.21(stat.) ± 0.23(syst.)) × 10 −6. The 90% confidence level upper limits on the branching fractions of the other modes having a significance of less than 3σ are determined. These results are consistent with theoretical calculations using the nonrelativistic QCD factorization approach.

Physical Review D, 2012

Using (106 ± 4) × 10 6 ψ ′ events accumulated with the BESIII detector at the BEPCII e + e − collider, we present measurements of the branching fractions for ψ ′ decays to K + K − π 0 and K + K − η. In these final states, the decay ψ ′ → K * 2 (1430) + K − + c.c. is observed for the first time, and its branching fraction is measured to be (7.12 ± 0.62 (stat.) +1.13 −0.61 (syst.)) × 10 −5 , which indicates a violation of the helicity selection rule in ψ ′ decays. The branching fractions of ψ ′ → K * (892) + K − + c.c., φη, φπ 0 are also measured. The measurements are used to test the QCD predictions on charmonium decays.

Physical Review D, 1986

Results from a detailed study using the Crystal Ball detector at the SLAC e+e storage ring SPEAR of the inclusive photon spectra from 1.8 X 106 i(t' and 2.2&& 106 J/P decays are presented. Radiative transitions from the P to the 1'2~o states are observed with photon energies of 126.0+0.2+4, 169.6+0.3 +4, and 258.4+0.4+4 Mev and branching ratios 8(i('~y X2, &, p) =(8.0%0.5+0.7)%, (9.0+0.5+0.7)%, and (9.9+0.5+0.8)%, respectively. Values for the natural linew'idths of the p states are obtained: I (p2 l 0)=0.8-4.9, &3.8, and 13-21 MeV, respectively (90% C.L.). Improved values are found for the branchmg ratios 8(g'~yg,) =(0.28+0.06)% and B(J//~yes,) =(1.27+0.36)%, and for the natural width I (g,) =11.524.5 MeV.

Physical Review Letters, 2001

In a sample of 9.66 × 10 6 BB pairs collected with the CLEO detector we make the first observation of B decays to an η c and a kaon. We measure branching fractions B

Physical Review Letters, 2010

Physical Review Letters, 2008

Physical Review D

Physical Review D, 1995

Massless perturbative QCD forbids, at leading order, the exclusive annihilation of proton-antiproton into some charmonium states, which, however, have been observed in the pp channel, indicating the significance of higher order and non perturbative effects in the few GeV energy region. The most well known cases are those of the 1 S 0 (η c ) and the 1 P 1 . The case of the 1 D 2 is considered here and a way of detecting such a state through its typical angular distribution in the radiative decay 1 D 2 → 1 P 1 γ is suggested. Estimates of the branching ratio BR( 1 D 2 → pp), as given by a quark-diquark model of the nucleon, mass corrections and an instanton induced process are presented.

Physical Review Letters, 2005

We report measurements of branching fractions and charge asymmetries of exclusive decays of neutral and charged B mesons into two-body final states containing a charmonium state and a light strange meson. The charmonium mesons considered are J/Psi, Psi(2S) and Chi_c1, and the light meson is either K or K*. We use a sample of about 124 million BBbar events collected with the BABAR detector at the PEP-II storage ring at the Stanford Linear Accelerator Center.

Physical Review D, 1995

Massless perturbative QCD forbids, at leading order, the exclusive annihilation of a proton-antiproton pair into some charmonium states, which, however, have been observed in the pp¯ channel, indicating the significance of higher order and nonperturbative effects in the few GeV energy region. The most well known cases are those of the 1 S 0 (η c ) and the 1 P 1 . The case of the 1 D 2 is considered here and a way of detecting such a state through its typical angular distribution in the radiative decay 1 D 2 → 1 P 1 γ is suggested. Estimates of the branching ratio B( 1 D 2 →pp¯), as given by a quark-diquark model of the nucleon, mass corrections, and an instanton-induced process are presented.

Physical Review D, 1999

Hadronic decays of the P-wave spin-triplet charmonium states χ cJ (J = 0, 1, 2) are studied using a sample of ψ(2S) decays collected by the BES detector operating at the BEPC storage ring. Branching fractions for the decays