Revisiting the production of $J/ψ+η_c$ via the $e^+e^-$ annihilation within the QCD light-cone sum rules

Abstract

We make a detailed study on the typical production channel of double charmoniums, e + e − → J/ψ + ηc, at the center-of-mass collision energy √ s = 10.58 GeV. The key component of the process is the form factor FVP(q 2 ), which has been calculated within the QCD light-cone sum rules (LCSR).To improve the accuracy of the derived LCSR, we keep the J/ψ light-cone distribution amplitude up to twist-4 accuracy. Total cross sections for e + e − → J/ψ + ηc at three typical factorization scales are σ|µ s = 22.53 +3.46 −3.49 fb, σ|µ k = 21.98 +3.35 −3.38 fb and σ|µ 0 = 21.74 +3.29 −3.33 fb, respectively. The factorization scale dependence is small, and those predictions are consistent with the BABAR and Belle measurements within errors.

Next-to-next-to-leading-order QCD corrections to J/ψ plus ηc production at the B factories

“…this discrepancy, such as the light-cone factorization approach [20][21][22] or light-cone sum rules [23,24]. The next-to-leading-order (NLO) QCD correction of the process has been regarded as a breakthrough [25,26], which can greatly enhance the size of cross section and reduce the large discrepancy.…”

The $D_s$-meson leading-twist distribution amplitude within the QCD sum rules and its application to the $B_s \to D_s$ transition form factor

“…Till now, there are few calculations on the D s -meson leading-twist LCDA φ 2;Ds ; recently, it has been studied by using the light-front quark model [35]. We shall first construct a light-cone harmonic oscillator model for φ 2;Ds based on the well-known BHL-description [36][37][38] as we have done for π, ρ, D and heavy meson LCDAs [39][40][41][42][43][44][45][46]. Then its input parameters shall be fixed by using reasonable constraints such as the probability of finding the leading Fock-state in D s -meson Fock-state expansion, the normalization condition, and the calculated LCDA moments ξ n 2;Ds or the Gegenbauer moments a Ds n .…”