相关论文: Power counting and effective field theory for char…

NRQCD results for Upsilon and Charmonium using both dynamical and quenched configurations are presented. We investigate dependence on the light dynamical quark mass. Preliminary dynamical ($n_f = 2$) Charmonium data are combined with…

We generalize results of lattice QCD to determine the spin-dependent symmetries and factorization properties of meson production in OZI allowed processes. This explains some conjectures previously made in the literature about axial meson…

We study QCD in 1+1 dimensions in the large $N_c$ limit using light-front Hamiltonian perturbation theory in the $1/N_c$ expansion. We use this formalism to exactly compute hadronic transition matrix elements for arbitrary currents at…

The hyperfine spin splittings in heavy quarkonia are studied using the recently developed renormalization group improved spin-spin potential which is independent of the scale parameter $\mu$. The calculated energy difference between the…

We compute the $J/\psi$ polarization observables $\lambda_\theta$, $\lambda_\phi$, $\lambda_{\theta\phi}$ in a Color Glass Condensate (CGC) + nonrelativistic QCQ (NRQCD) formalism that includes contributions from both color singlet and…

In the framework of perturbative QCD and potential models of heavy quarkonium, total cross-sections and differential characteristics of hadronic production for different spin states of the $B_c$-meson family are calculated at energies of…

In this talk I review some recent applications of NRQCD. I first discuss the unquenched NRQCD lattice extractions of the strong coupling constant, paying particular attention to the recent advances in reducing systematic errors. I then…

We introduce the contributions to the proceedings of Working Group V. The main topics were: present and future experiments dedicated to charm physics, the interplay between high-precision measurements and better control over theoretical…

The good agreement between large-scale observations and the predictions of the now-standard $\Lambda$CDM theory gives us hope that this will become a lasting foundation for cosmology. After briefly reviewing the current status of the key…

We compute leading-power fragmentation corrections to $J/\psi$ photoproduction at DESY HERA, making use of the nonrelativistic QCD factorization approach. Our calculations include parton production cross sections through order $\alpha_s^3$,…

Within the nonrelativistic QCD (NRQCD) factorization framework, we have computed the ${\mathcal O}(\alpha_s^2)$ corrections to the exclusive production of $P$-wave spin-triplet charmonia $\chi_{cJ}(J=0,1,2)$ accompanied by a hard photon at…

The Lambda_b to Lambda_c semileptonic decay is analyzed in the framework of heavy quark effective theory to the order of 1/m_c and 1/m_b. The QCD sum rule and large N_c predictions to the decay form factors are applied. It argues that the…

In a recent paper [1] a master formula has been presented for the power counting of a general effective field theory. We first show that this master formula follows immediately from the concept of chiral dimensions (loop counting), together…

The one-loop QCD heavy quark potential is computed to order v^2 in the color singlet and octet channels. Several errors in the previous literature are corrected. To be consistent with the velocity power counting, the full dependence on |p'…

Nonrelativistic quark models of charmonia are tested by comparison of theoretical charmonium decay constants, form factors, and $\gamma\gamma$ widths with experiment and lattice gauge computations. The importance of relativistic effects, a…

We study $\chi_{cJ}\to VV$ decays using the QCD effective field theory approach. The helicity suppressed decay amplitudes are also considered. The colour-singlet contributions of these amplitudes suffer from the endpoint singularities, it…

A simple parametrization of the QCD running coupling at low scales is introduced and used to illustrate various schemes for the estimation of non-perturbative power corrections. The `infrared matching' scheme proposed earlier gives…

The proton energy spectrum and the angular distribution of the probability of the $\Lambda^+_c$ -> p + $K^-$ + $\pi^+$ decay for the polarized $\Lambda^+_c$ and the unpolarized proton are calculated in the effective quark model with chiral…

Due to the heavy-quark symmetry of Non-Relativistic Quantum Chromodynamics (NRQCD), the cross-section for the production of $\eta_c$ can be predicted. This NRQCD prediction when confronted with data from the LHCb is seen to fail miserably.…

In this contribution we summarize experimental information and theoretical results for the dissociation cross sections of charmonium by light hadrons. Theoretical predictions for these RHIC-related processes differ by orders of magnitude…