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We study the Јg*g* vertex for arbitrary gluon virtualities in the timelike and spacelike regions, using the perturbative QCD hard scattering approach and an input wave function of the Ј meson consistent with the measured Ј␥*␥ transition form factor. The contribution of the gluonic content of the Ј meson is taken into account, enhancing the form factor over the entire virtuality considered. However, data on the electromagnetic transition form factor of the Ј meson are not sufficient to quantify the gluonic enhancement. We also study the effect of the transverse momenta of the partons in the Ј meson on the Јg*g* vertex, using a modified hard scattering approach based on the Sudakov formalism, and contrast the results with the ones in the standard hard scattering approach in which such effects are neglected. Analytic expressions for the Јg*g* vertex are presented in limiting kinematic regions and parametrizations are given satisfying the QCD anomaly, for real gluons, and perturbative QCD behavior for large gluon virtualities, in both the timelike and spacelike regions. Our results have implications for the inclusive decay B→ЈX and exclusive decays, such as B→Ј(K,K*), and for hadronic production processes NϩN(N )→ЈX.

Recently, the LHCb Collaboration have updated their analysis of the resonant J/ψ p mass spectrum in the decay Λ 0 b → J/ψ p K − . In the combined Run 1 and Run 2 LHCb data, three peaks are observed, with the former P c (4450) + state split into two narrow states, P c (4440) + and P c (4457) + , having the masses M = (4440.3 ± 1.3 +4.1 −4.7 ) MeV and M = (4457.3 ± 0.6 +4.1 −1.7 ) MeV, and decay widths Γ = (20.6 ± 4.9 +8.7 −10.1 ) MeV and Γ = (6.4 ± 2.0 +5.7 −1.9 ) MeV, respectively. In addition, a third narrow peak, P c (4312) + , having the mass M = (4311.9 ± 0.7 +6.8 −0.6 ) MeV and decay width Γ = (9.8 ± 2.7 +3.7 −4.5 ) MeV is also observed. The LHCb analysis is not sensitive to broad J/ψ p contributions like the former P c (4380) + , implying that there could be more states present in the data. Also the spin-parity, J P , assignments of the states are not yet determined. We interpret these resonances in the compact diquark model as hiddencharm diquark-diquark-antiquark baryons, having the following spin and angular momentum quantum numbers: P c (4312) + = {c[cu] s=1 [ud] s=0 ; L P = 0, J P = 3/2 − }, the S-wave state, and the other two as P -wave states, with P c (4440) + = {c[cu] s=1 [ud] s=0 ; L P = 1, J P = 3/2 + } and P c (4457) + = {c[cu] s=1 [ud] s=0 ; L P = 1, J P = 5/2 + }. The subscripts denote the spins of the diquarks and L P = 0, 1 is the orbital angular momentum quantum number of the pentaquark. These assignments are in accord with the heavy-quark-symmetry selection rules for Λ b -baryon decays, in which the spin S = 0 of the light diquark [ud] s=0 is conserved. The masses of observed states can be accommodated in this framework and the two heaviest states have the positive parities as opposed to the molecular-like interpretations. In addition, we predict several more states in the J/ψ p mass spectrum, and urge the LHCb Collaboration to search for them in their data.

We study the implication of the recent measurement by the BELLE collaboration of the averaged branching fractionB exp [B → (ρ, ω) γ] = (1.8 +0.6 −0.5 ± 0.1) × 10 −6 for the CKM phenomenology. Combined with the averaged branching fractionB exp (B → K * γ) = (4.06 ± 0.26) × 10 −5 measured earlier, this yieldsR exp [(ρ, ω) γ/K * γ] = (4.2 ± 1.3)% for the ratio of the two branching fractions. Updating earlier theoretical analysis of these decays based on the QCD factorization framework, and constraining the CKM-Wolfenstein parameters from the unitarity fits, our results yieldB th [B → (ρ, ω) γ] = (1.38 ± 0.42) × 10 −6 andR th [(ρ, ω) γ/K * γ] = (3.3 ± 1.0)%, in agreement with the BELLE data. Leaving instead the CKM-Wolfenstein parameters free, our analysis gives (at 68% C.L.) 0.16 ≤ |V td /V ts | ≤ 0.29, which is in agreement with but less precise than the indirect CKM-unitarity fit of the same, 0.18 ≤ |V td /V ts | ≤ 0.22. The isospin-violating ratio in the B → ργ decays and the SU(3)-violating ratio in the B 0 d → (ρ 0 , ω) γ decays are presented together with estimates of the direct and mixing-induced CP-asymmetries in the B → (ρ, ω) γ decays within the SM. Their measurements will overconstrain the angle α of the CKM-unitarity triangle.

We provide the definition of the complete set of light-cone distribution amplitudes (LCDAs) for the ground state heavy bottom baryons with the spin-parities J P = 1/2 + and J P = 3/2 + in the heavy quark limit. We present the renormalization effects on the twist-2 light-cone distribution amplitudes and use the QCD sum rules to compute the moments of twist-2, twist-3, and twist-4 LCDAs. Simple models for the heavy baryon distribution amplitudes are analyzed with account of their scale dependence. IntroductionPrecision tests of the unitarity of the quark mixing matrix remain high on the agenda of flavor physics. They allow to pin down the Standard Model (SM) description of CP-violation and may reveal physics beyond the SM (BSM). On the experimental side, the two B-meson factories at SLAC and KEK, after approximately a decade of their operation, have made a great impact on the origin of CP-violation in the quark sector of the SM. Especially in b physics, the B-factory experiments BABAR and BELLE have concentrated on the production and decays of the bb resonances, Υ (4S) and Υ (5S), yielding precise measurements of their decay products, the B-and theB-mesons. Theoretically, inclusive decays of the B-mesons, such as the radiative and semileptonic decays, are under quantitative control, thanks to the use of the Heavy Quark Effective Theory (HQET), allowing an expansion in the inverse b-quark mass, with perturbative QCD allowing to calculate corrections in α s (m b ) to each order in 1/m b . Exclusive semileptonic and radiative decays require, on the other hand, a precise knowledge of the non-perturbative quantities -the decay form factors -to be analyzed precisely. However, also in such cases, the large energy released in the B → hX decays, where h is a light meson and X = γ, + − , ± ν , allows to relate several of these form factors. The resulting large energy effective theory (LEET), which has been replaced by a more systematic effective theory, the Soft