Related papers: Direct Fragmentation of Quarkonia Including Fermi …
The processes of P-wave Quarkonium exclusive decays to two mesons are investigated, in which the final state vector mesons with various polarizations are considered separately. In the calculation, the initial heavy quarkonia are treated in…
The fragmentation function of a scalar leptoquark into possible S-wave bound states with a heavy anti-quark is calculated to the leading order in perturbative QCD for the high energy processes at large transverse momenta. The one-loop…
We investigate the electromagnetic structure of heavy quarkonia and the $B_c$ meson within the light-front quark model (LFQM) to better understand the internal spatial charge distributions and QCD dynamics of heavy mesons. The light-front…
Diffractive dissociation of particles can be used to study their light-cone wave function. Results from Fermilab experiment E791 for diffractive dissociation of 500 GeV/c $\pi^-$ mesons into di-jets are presented. The results show that the…
We calculate the polarisation of $\psi$'s and $\Upsilon$'s produced by the fragmentation of heavy quarks. We find that fragmentation to transversely aligned quarkonium is slightly enhanced relative to longitudinally polarised. This net…
The fragmentation functions for gluons to split into P-wave heavy quarkonium states are calculated to leading order in the QCD coupling constant. Long-distance effects are factored into two nonperturbative parameters: the derivative of the…
The dominant mechanism to produce hadronic bound states with large transverse momentum is fragmentation, that is the splitting of a high energy parton into a hadronic state and other partons. We review the present schemes to calculate the…
The process AB --> Quarkonium + photon + X, for a heavy quarkonium state such as J/psi or Upsilon, is considered. The ratio of the cross-sections for this process in pp and pp(bar) collisions is shown to be a vary sensitive probe of models…
We reexamine the Fermi motion effects on the diffractive photo- and electroproductions of heavy vector-mesons, J/psi and psi', off a nucleon in the leading ln(Q^2/Lambda_QCD^2) approximation (LLA) of QCD. We take into account all the Fermi…
We investigate the non-trivial 3-momentum effects on the masses of heavy quarkonium states that are moving in a hot medium using QCD sum rules. For all charmonium states, we observe a negative mass shift near $T_c$ that is less than 3$\%$…
Diffractive production of J/Psi particles by virtual photons on a proton target is studied with a view towards understanding two important corrections to the leading order result. First, the effect of Fermi motion of the heavy quarks is…
The recent development of perturbative QCD (PQCD) fragmentation functions has strong impact on quarkonium production. I shall summarize $B_c$ meson production based on these PQCD fragmentation functions, as well as, the highlights of some…
We investigate the reaction gamma+p -> V+p, with V denoting a Phi or a J/Psi meson, within the scope of perturbative QCD, treating the proton as a quark-diquark system. Our predictions extrapolate the existing forward differential…
Diffractive production of $J/\Psi$ particles by virtual photons on a proton target is studied with a view towards understanding two important corrections to the leading order result. First, the effect of Fermi motion of the heavy quarks is…
Heavy quarkonium production is a powerful implement to study the strong interaction dynamics and QCD theory. Fragmentation is the dominant production mechanism for heavy quarkonia with large transverse momentum. With the large heavy quark…
It is pointed out that the diagonal amplitude of the $E1-E1$ chromo-electric interaction with soft gluon fields (chromo-polarizability) can be measured directly for the $J/\psi$ and $\Upsilon$ resonances in the decays $J/\psi \to \pi \pi…
We studied the properties of the heavy quarkonia in the presence of finite quark-chemical potential for different number of flavors by using the quasi particle approach. The effect of the finite quark-chemical potential has been…
Heavy quarkonia in a homogeneous magnetic field are analyzed by using a potential model with constituent quarks. To obtain anisotropic wave functions and corresponding eigenvalues, the cylindrical Gaussian expansion method is applied, where…
We compute fragmentation corrections to hadroproduction of the quarkonium states $J/\psi$, $\chi_{cJ}$, and $\psi(2S)$ at leading power in $m_c^2/p_T^2$, where $m_c$ is the charm-quark mass and $p_T$ is the quarkonium transverse momentum.…
Hard diffractive photo- and electroproduction of heavy vector mesons ($J/\psi$ and $\Upsilon$) is evaluated within the leading $\alpha_s\ln{Q^2 \over\Lambda_{QCD}^2}$ approximation of QCD. In difference from our earlier work on that…