NLO corrections toχbJto two-J/ψexclusive decay processes

Abstract

The next-to-leading order QCD corrections for χ bJ , the p-wave bottomonium, to J/ψ pair decay processes are evaluated utilizing NRQCD factorization formalism. The scale dependence of χ b2 → J/ψJ/ψ process is depressed with NLO corrections, and hence the uncertainties in the leading order results are greatly reduced. The total branch ratios are found to be the order of 10 −5 for all three χ bJ → J/ψJ/ψ processes, indicating that they are observable in the LHC and super-B experiments.

NLO QCD corrections to exclusive quarkonium-pair production in photon–photon collision

“…[8], the leading order (LO) calculation of exclusive J/ψ-pair production via photon-photon fusion was performed within the NRQCD factorization framework, while the J/ψ-pair diffractive production was investigated in the pomeron exchange scheme [9][10][11][12]. Considering the fact that the next-to-leading order (NLO) QCD corrections to physical processes in quarknoium energy regime are normally significant [13][14][15][16], in this work we calculate γ + γ → Q + Q processes, where Q = J/ψ, η c , ϒ, or η b , at the NLO accuracy.…”

NLO QCD Corrections for $χ_{cJ}$ Inclusive Production at $B$ Factories

“…NLOχ [8] c2 µ = 2m c 1.82 comes from the color-singlet configuration, while for χ c1 and χ c2 production the coloroctet contributes more. After adding all the channels of this work, the NLO inclusive production cross sections at µ = 3GeV for χ cJ (J = 0, 1, 2) are 91.17fb, 24.61fb and 35.15fb, respectively.…”

“…It seems so far that most of the discrepancies between LO calculation and experimental observation can be rectified by including higher order corrections, which has encouraged more NLO QCD calculations on quarkonium production and decay. On this point, one typical example is the double charmonium production at B factories [2][3][4][5][6][7][8].…”

“…Infrared divergences arising from loop integration, phase space and counter terms are partially canceled with each other. For J production processes one obtains divergent terms proportional to the Born level amplitude of the color-octet 3 S [8] 1 process, and these divergent terms are then attributed to the NLO color-octet NRQCD matrix elements…”

NLO QCD corrections to $J/ψ$ pair production in photon-photon collision

“…[8], the leading order (LO) calculation of exclusive J/ψ pair production via photon-photon fusion was performed within the NRQCD factorization framework, while the J/ψ pair diffractive production was investigated in the pomeron exchange scheme [9][10][11][12]. Considering the fact that the next-to-leading order (NLO) QCD corrections to physical processes in quarknoium energy regime are normally significant [13][14][15][16], in this work we calculate the γ + γ → J/ψ + J/ψ process at the NLO accuracy.…”