相关论文: The $p_T$ Distribution of $J/\psi$ in QGP
Color-octet contributions to the associate J/psi+gamma hadroproduction are studied in detail, and found to be negligible, compared to the ordinary color-singlet contribution. Within the color-singlet model the J/psi+gamma production in the…
J/psi production in top quark rare decays is investigated under the framework of NRQCD factorization formalism. Various production channels are studied, and we find that the contributions from the color-singlet quark fragmentation and the…
We study contributions from color-octet quarkonium formation mechanisms to $J/\psi$ hadroproduction at low $p_\perp$. We include transitions of color-octet $c\bar{c}$ states into ``direct'' $J/\psi$ and into $\chi_{1,2}$ which decay…
We review the search for the quark-gluon plasma using the signal of the suppression of J/psi production in high-energy heavy-ion collisions. Recent observations of anomalous J/psi suppression in high-energy Pb-Pb collisions observed by the…
The J/psi is considered to be among the most important probes for the deconfined quark gluon plasma (QGP) created by relativistic heavy ion collisions. While the J/psi is thought to dissociate in the QGP by Debye color screening, there are…
We show that the colour-singlet contributions to the hadroproduction of J/psi in association with a W boson are sizable, if not dominant over the colour-octet contributions. They are of two kinds, sg -> J/psi + c + W at alpha^3_S alpha and…
The remarkable discrepancy between theory and data on the p_t distribution of J/psi polarization in the process pp -> J/psi+X has been standing as a puzzle for a long time. Our early work indicates that if only considering the color-singlet…
We consider the energy and the polar angle distributions of J/\psi's produced via the color-singlet and the color-octet (^3S_1^{(8)}) mechanisms in Z^0 \to J/\psi +X at LEP. Since both distributions of the J/\psi produced via color-octet…
$J/\psi$ suppression in p-A collisions is studied by considering the nuclear effects on parton distribution, energy loss of beam proton and the finial state energy loss of color octet $c\overline{c}$. The leading-order computations for…
We propose the color-octet mechanism combined with the two gluon exchange model for the diffractive $J/\psi$ production in hadron collisions. In the leading logarithmic approximation (LLA) in QCD, we find that the diffractive $J/\psi$…
Photoproduction of $J/\psi$ is considered including the color-octet contributions from the various partial wave states, $^{2S+1}L_J$ = $^1S_0$, $^3S_1$ and $^3P_J$. The production cross section depends on three new nonperturbative…
We compute \frac{d\sigma}{dp_T} of the J/\psi production in pp collisions at RHIC at \sqrt s = 500 and 200 GeV by using both the color octet and singlet models in the framework of non-relativistic QCD. The J/\psi we compute here includes…
The transverse momentum ($p_t$) distributions of production and polarization for $J/\psi$ measured by CDF Collaboration are still challenging our understanding of the heavy quarkonium production mechanism even with recent significant…
We investigate $J/\psi$ photoproduction asymmetries in the framework of the NRQCD factorization approach. It is shown that the color octet contribution leads to large uncertainties in the predicted asymmetries which rules out the…
We investigate $J/\psi$ photoproduction asymmetries in the framework of the NRQCD factorization approach. It is shown that the color octet contribution leads to large uncertainties in the predicted asymmetries which rules out the…
The suppression of heavy quarkonia e.g. $J/\psi$, $\Upsilon$ etc. is considered as a suitable probe to identify the nature of the matter created in heavy ion collisions. Recently we have presented a modified colour screening model for…
The NA50 Collaboration has recently observed a strong suppression of J/Psi production in Pb-Pb collisions at 158 Gev/n. We show that this recent observation finds a quantitative explanation in a model which relates the suppression mechanism…
To test a possible color-octet contribution of heavy quarkonium productions, we propose $\psi$'-productions for small-$p_T$ regions, where the color-singlet $\psi$' state cannot be produced by the gluon-gluon fusion owing to charge…
We calculate the direct production rate of $J/\psi$ in top quark decays. The color-octet $J/\psi$ production via $t\rightarrow W^+ b J/\psi$ is shown to have a large branching ratio of order $1.5\times 10^{-4}$, which is over an order of…
We present an analysis of the \psi\psi production from double parton (DP) sacttering and single parton (SP) scattering in the large p_T region via color-octet gluon fragmentation. We find that at the Tevatron the DP \psi\psi production is…