相关论文: Direct Fragmentation of Quarkonia Including Fermi …
We investigate the relativistic Fermi motion effect in the case of $J/\psi$ production in various hadron colliders. A light-cone wave function is adopted to represent the $J/\psi$ final state. The change in the confinement parameter which…
In the paper, we derive the next-to-leading order (NLO) fragmentation function for a heavy quark, either charm or bottom, into a heavy quarkonium $J/\Psi$ or $\Upsilon$. The ultra-violet divergences in the real corrections are removed…
The production of heavy quarkonia is a powerful tool to test our understanding of strong interaction dynamics. It is well-known that the dominant production mechanism for heavy quarkonia with large transverse momentum is fragmentation. In…
We present a novel study on the inclusive production of a heavy quarkonium ($J/\psi$ or $\Upsilon$), in association with a light-flavored jet, as a test field of the high-energy QCD dynamics. The large transverse momenta at which the two…
We investigate the inclusive hadroproduction of a heavy quarkonium ($J/\psi$ or $\Upsilon$), in association with a light-flavored jet, as a testing ground for the semi-hard regime of QCD. Our theoretical setup is the hybrid high-energy and…
After a brief review on how heavy quark symmetry constraints the helicity fragmentation probabilities for a heavy quark hadronizes into heavy-light hadrons, we present a heavy quark fragmentation model to extract the value for the…
The Fermi motion effect in $J/\psi$ production in various hadron colliders is studied. We deduce that in agreement with sum rules which the fragmentation functions should satisfy, while the effect has considerable influence on the…
We analyze the uncertainties induced by different definitions of the momentum fraction $z$ in the application of gluon to heavy quarkonium fragmentation function. We numerically calculate the initial $g \to J / \psi$ fragmentation functions…
We make comments on ref.[Z.Phys. C73, 541 (1997)], and provide partial wave analysis to the decays of excited heavy S-wave $1^-$ quarkonia into the basic $1^-$ quarkonia state plus $\pi\pi$. It is revealed that there exist contributions of…
Light-cone Fock-state wavefunctions encode the properties of a hadron in terms of its fundamental quark and gluon degrees of freedom. A recent experiment at Fermilab, E791, demonstrates that the color coherence and shape of light-cone…
In a previous paper \cite{Bc}, it was pointed out that the wave functions of all particles are not pure waves, besides the main partial waves, they all contain {other partial waves}. It is very interesting to know what role these different…
Heavy and light quarks produced in high-$p_T$ partonic collisions radiate differently. Heavy quarks regenerate their color field, stripped-off in the hard reaction, much faster than the light ones and radiate a significantly smaller…
At the large transverse momentum region, the production of heavy-heavy bound-states such as charmonium, bottomonium, and $\bar bc$ mesons in high energy $e^+e^-$ and hadronic collisions is dominated by parton fragmentation. We calculate the…
The ensemble of light-cone Fock wavefunctions $\{\psi_{n/H}(x_i,\vec k_{\perp i},\lambda_i)\}$ provides a conceptual basis for representing physical hadrons and nuclei in terms of their fundamental quark and gluon degrees of freedom. A…
In the fragmentation of a heavy quark into a heavy meson whose light degrees of freedom have angular momentum $3/2$, all the helicity probabilities are completely determined in the heavy quark limit up to a single probability $w_{3/2}$. We…
Several fixed-target experiments reported J/$\psi$ and $\Upsilon$ polarization measurements, as functions of Feynman $x$ ($x_{\rm F}$) and transverse momentum ($p_{\rm T}$), in three different polarization frames, using different…
New double ratios of exponential moments of different two-point functions, which are less sensitive to the heavy quark mass and to the continuum effects than the commonly used ratio of moments, are presented for a more refined analysis of…
In a transient magnetic field, heavy quarkonium bound states evolve non adiabatically. In presence of a strong magnetic field, $J/\Psi$ and $\Upsilon(1S)$ become more tightly bound than we expected earlier for a pure thermal medium. We have…
Diffractive dissociation of particles can be used to study their light-cone wave functions. Results from Fermilab experiment E791 for diffractive dissociation of 500 GeV/c pi- mesons into di-jets show that the |q qbar> light-cone asymptotic…
The perturbative QCD fragmentation functions for a heavy quark to fragment into heavy-light mesons are studied in the heavy-quark limit. The fragmentation functions for S-wave pseudoscalar and vector mesons are calculated to next-to-leading…