Related papers: Inclusive $J/\psi$ Productions at $e^+ e^-$ Collid…
We discuss prompt production of $J/\psi$ mesons in proton-proton collisions at the LHC within NRQCD k$t$-factorization approach using Kimber-Martin-Ryskin (KMR) and Kutak-Stasto (KS) unintegrated gluon distribution (UGDF). We include both…
The production of prompt $J/\psi$, $\psi(2S)$, $\chi_{c1}$ and $\chi_{c2}$ is studied using a $32.4 fb^{-1}$ data sample collected with the Belle detector at the $\Upsilon(4S)$ and 60 MeV below the resonance. The yield of prompt $J/\psi$…
We review the current theoretical situation with regard to the anomalously large cross section for exclusive J/psi + eta_c production in e^+ e^- annihilation, as measured by BELLE Collaboration.
A new measurement of the b-bbar production cross section in 920 GeV proton-nucleus collisions is presented by the HERA-B collaboration. The b-bbar production is tagged via inclusive bottom quark decays into J/psi mesons, by exploiting the…
$J/\psi$ suppression with rapidity is studied with both (3+1) dimensional transport equation and hydrodynamics in details at $\sqrt{s_{NN}}=2.76$ TeV Pb+Pb collisions. In central rapidity region of the hot medium, $J/\psi$ nuclear…
The J/$\psi$ $\to$ $\mu^+\mu^-\mu^+\mu^-$ decay has been observed with a statistical significance in excess of five standard deviations. The analysis is based on an event sample of proton-proton collisions at a center-of-mass energy of 13…
In the ALICE experiment, at forward rapidity (2.5 < y < 4), the production of heavy quarkonium states is measured via their mu+ mu- decay channels. We present the first measurement of inclusive J/Psi production, down to pT = 0, from Pb-Pb…
The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at sqrt{s}=7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L_int = 5.6nb-1. The fraction of J/psi…
We present a study of the inclusive J/psi cross section at 2.76 TeV and 5.5 TeV. The energy dependence of the cross section, rapidity and transverse momentum distributions are evaluated phenomenologically. Their knowledge is crucial as a…
It is shown that difficulties in reconciling the values of the cross section e+e- -> J/psi+eta_c measured at BELLE and calculated within non-relativistic QCD (NRQCD) are caused not by some misinterpretation of the data or other exotic…
The process e+e- to K+K-J/psi is observed for the first time via initial state radiation. The cross section of e+e- to K+K-J/psi for center-of-mass energies between threshold and 6.0 GeV is measured using 673 fb^{-1} of data collected with…
The ALICE Collaboration at the LHC has measured the J/$\psi$ and $\psi^{'}$ photoproduction at mid-rapidity in ultra-peripheral Pb-Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV. The charmonium is identified via its leptonic decay for events…
We use a new approach to color evaporation model (CEM) for quarkonium production. The production of $c\bar c$ pairs is performed within $k_T$-factorization approach using different unintegrated gluon distribution functions (UGDF) from the…
We study the production and polarization of $J/\psi$ mesons within a jet in proton-proton collisions at the LHC. We define the $J/\psi$-jet fragmentation function as a ratio of differential jet cross sections with and without the…
We have analyzed the NA58 data on $J/\psi$ suppression in Pb+Pb collisions. $J/\psi$ production is assumed to be a two step process, (i) formation of $c\bar{c}$ pair, which is accurately calculable in QCD and (ii) formation of $J/\psi$…
This paper is devoted to the study of the processes e^+e^- \to J/\Psi \eta_c, J/\Psi \eta_c', \psi' \eta_c, \psi' \eta_c' within light cone formalism. It is shown that if one disregards the contribution of higher fock states, the twist-3…
The inclusive $J/\psi$ transverse momentum ($p_{T}$) spectra and nuclear modification factors are reported at midrapidity ($|y|<1.0$) in Au+Au collisions at $\sqrt{s_{NN}}=$ 39, 62.4 and 200 GeV taken by the STAR experiment. A suppression…
The interpretation of the J/psi suppression patterns observed in nuclear collisions, at CERN and RHIC, as a signature of the formation of a deconfined phase of QCD matter, requires knowing which fractions of the measured J/psi yields, in pp…
The inclusive production of the J/$\psi$ and $\psi$(2S) charmonium states is studied as a function of centrality in p-Pb collisions at a centre-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}} = 8.16$ TeV at the LHC. The measurement is…
We have studied the J/psi suppression in 158 GeV/c Pb+Pb collisions at CERN SPS. J/psi production is assumed to be a two step process, (i) formation of c bar{c} pair, which is accurately calculable in QCD and (ii) formation of J/psi meson…