Exclusive decay ofΥintoJ/ψ+χc0,1,2

Abstract

We study the Ç exclusive decay into double charmonium, specifically, the S-wave charmonium J=c plus the P-wave charmonium c0;1;2 in the nonrelativistic QCD factorization framework. Three distinct decay mechanisms, i.e., the strong, electromagnetic, and radiative decay channels, are included, and their interference effects are investigated. The decay processes Çð1S; 2S; 3SÞ ! J=c þ c1;0 are predicted to have the branching fractions of order 10 À6 , which should be observed in the prospective Super B factory.

Evidence ofϒ(1S)→J/ψ+χc1and sear

“…The branching fractions are predicted to be of order 10 −6 for Υ(nS) → J/ψ(ψ ′ ) + η c (η c (2S)) (n = 1, 2, 3) [31]; for Υ → J/ψ + η c , in particular, the predicted branching fraction is consistent with the previous calculation of 1.7 × 10 −6 with only the three-gluon contribution considered [33]. For the J/ψ + χ c0,1,2 decay modes, the branching fractions are calculated at the lowest order [32]; that of Υ(nS) → J/ψ + χ c1 is the largest-of order 10 −6 -while that of J/ψ + χ c2 is only of order 10 −7 . In this paper, we report studies of exclusive hadronic decays of Υ(1S) and Υ(2S) resonances to the double-charmonium final states J/ψ(ψ ′ ) + X, where X 6 is one of the η c , χ cJ (J = 0, 1, 2), η c (2S), X(3940), and X(4160) states.…”

“…Compared with the Υ(4S) resonance with its rather broad width, the first three Υ resonances are so narrow that the resonant decay contributions dominate over the continuum ones. This provides a further opportunity to probe the potential properties of double-charmonium production at these Υ peaks.Comprehensive studies of the exclusive decay of Υ into a vector-plus-pseudoscalar charmonium[31], as well as the S-wave charmonium J/ψ plus the P-wave charmonium χ cJ (J = 0, 1, 2) [32] have been performed in the NRQCD factorization approach, where the contributions from the strong, electromagnetic, and radiative channels were considered and the strong decay was taken as dominant. The branching fractions are predicted to be of order 10 −6 for Υ(nS) → J/ψ(ψ ′ ) + η c (η c (2S)) (n = 1, 2, 3) [31]; for Υ → J/ψ + η c , in particular, the predicted branching fraction is consistent with the previous calculation of 1.7 × 10 −6 with only the three-gluon contribution considered [33].…”

“…[31], as well as the S-wave charmonium J/ψ plus the P-wave charmonium χ cJ (J = 0, 1, 2) [32] have been performed in the NRQCD factorization approach, where the contributions from the strong, electromagnetic, and radiative channels were considered and the strong decay was taken as dominant. The branching fractions are predicted to be of order 10 −6 for Υ(nS) → J/ψ(ψ ′ ) + η c (η c (2S)) (n = 1, 2, 3) [31]; for Υ → J/ψ + η c , in particular, the predicted branching fraction is consistent with the previous calculation of 1.7 × 10 −6 with only the three-gluon contribution considered [33].…”

Exclusive decay of the upsilon intohc, theX(3940)andX(Zhu1 2015Phys. Rev. D130110View full textAdd to dashboardCite

“…Double-charmonium production has attracted a large amount of attention among theorists and experimentalists in the last ten years, especially the large discrepancy between theory [7][8][9][10] and data [11,12] in the B factory, that is later solved through QCD corrections [13][14][15][16][17]. In recent years, some exclusive decay channels of bottomonium into double charmonia have been investigated intensively, e.g., Υ → J/ψ + η c [18][19][20], [29]. The branching fractions of these channels are predicted to be order from 10 −6 to 10 −8 in the above literatures.…”

NLO corrections toχbJto two-J/ψexclusive decay processes

“…As in bottomonium to J/ψ pair exclusive decay processes the color-octet contribution is negligible, the theoretical evaluation result is quite explicit in comparison with the experimental data. The decays of η b to double J/ψ [11][12][13][14], Υ to J/ψ + χ cJ [15], and χ bJ to double J/ψ [16][17][18] had been thoroughly investigated. The process χ bJ → J/ψJ/ψ(J = 0, 2) was evaluated in the frameworks of NRQCD and light cone distribution amplitude at the leading order in α s expansion, except χ b1 → J/ψJ/ψ process.…”