Related papers: Evolution Effects in Z^0 Fragmentation into Charmo…

We study the systematic inclusion of QED corrections in the evolution of parton distributions. O(alpha) corrections modify the evolution equation for parton distributions. They introduce additional parton distributions, like the photon…

The color evaporation model simply states that charmonium production is described by the same dynamics as $D \bar D$ production, {\em i.e.}, by the formation of a colored $c \bar c$ pair. Its color happens to be bleached by soft final-state…

We investigate higher order symplectic integration strategies within Bayesian cosmic density field reconstruction methods. In particular, we study the fourth-order discretisation of Hamiltonian equations of motion (EoM). This is achieved by…

We calculate the long-distance matrix elements for the decays of the lowest-lying S- and P-wave states of charmonium and bottomonium in quenched lattice QCD, using a nonrelativistic formulation for the heavy quarks. (The short-distance…

Charmonium productions in $p-p$ and $A-B$ collisions have been estimated within the ambit of colour evaporation model (CEM). The model parameters have been fixed by fitting the theoretical results with CDF data. The method is then applied…

We assume universal values for the color-singlet ($\epsilon_1$) and color octet ($\epsilon_8$) nonfactorization parameters in B Decays. Two sets of color-favored processes and one set of color-suppressed processes were used to give…

In this paper we present a complete next-to-leading order QCD calculation of the $\chi_J$ ($^3P_J\; ;J=0,1,2$) hadronic decay width. We include the NLO colour-octet contribution, as defined in the Bodwin, Braaten and Lepage formalism. We…

By analyzing existing data on pseudoscalar charmonium decays, we obtain the ratio of the branching fractions of $\eta_c(2S)$ and $\eta_c$ decays into ten different final states with light hadrons. For the first time, we test the two…

We study the exclusive decays of $B$ meson into pseudoscalar charmonium states $\eta_c$ and $\eta_c^\prime$ within the QCD factorization approach and find that the nonfactorizable corrections to naive factorization are infrared safe at…

We summerize the status of factorization hypothesis in the color-suppressed B meson decays : $B \to J/\psi K^{(*)}$. We present the general formalism for decay rates and polarization fractions with considering all possible non-factorizable…

We study the possibility to probe the unpolarized and linearly polarized transverse momentum- dependent gluon distributions in unpolarized pp collision in charmonium and bottomonium produc- tion, employing non-relativistic QCD (NRQCD) based…

Recent theoretical progress in calculations of the spectrum and decays of charmonium is reviewed. Traditionally, our understanding of charmonium was based on potential models. This is now being replaced by first principles.

The decays pi^0, eta, eta-prime -> gamma gamma are investigated up to next-to-next-to-leading order in the framework of the combined 1/N_c and chiral expansions. Without mixing of the pseudoscalar mesons the N_c independence of the pi^0 and…

By employing the perturbative QCD (PQCD) factorization approach, we studied the sixteen $B/B_s \to \eta_c (\pi, K, \eta^{(\prime)},\rho,K^*,\omega,\phi)$ decays with the inclusion of the currently known next-to-leading order (NLO)…

We firstly address the recent efforts on calculations of the next-to-leading order corrections to the color-suppressed tree amplitude in QCD factorization method which may be essential to solve the puzzles in $B\to \pi\pi$ and $\pi K$…

The small x evolution of the QCD pomeron and the QCD odderon is investigated in the mean field limit of the Color Glass Condensate. The resulting system of coupled nonlinear evolution equations is transformed to the momentum space and…

We extract the B, D, and D* meson wave functions from the CLEO data of the decays B -> K*\gamma and B -> D^(*)\pi in the perturbative QCD framework. In this formalism, various logarithmic corrections are organized to give the Wilson…

In this study, the properties of the $J^{PC}=1^{++}$ hidden charm poles are analyzed under the variation of the bare 2P charmonium mass within the effective field theory proposed in Ref.[1]. The main focus of the current work is on the pole…

We investigate the $B\to\pi\rho$ and $\pi\omega$ decay processes using the modified perturbative QCD (PQCD) approach. Sudakov factors arising from the resummation of the double logarithms for the contributions of the transverse momenta of…

Using a sample of >10^5 J/psi to mu+mu- decays, Fermilab experiment 789 has studied production of J/psi and psi-prime in 800-GeV proton-nucleon collisions. Differential cross sections and nuclear dependences have been measured for…