相关论文: $J/\psi$ polarization in high multiplicity $pp$ an…

Both charm and bottom quarks form nonrelativistic bound states analogous to positronium. The J/psi and psi(2S) charmonium states and the first three Upsilon(nS) bottomonium states, all spin-triplet S-wave quarkonium states below…

We study $J/\Psi$ absorption in high multiplicity proton-proton (pp) collisions at $\sqrt {s_{NN}}=7\,$TeV. We predict a modification of the $J/\Psi$-yield within the UrQMD transport approach, where explicit interactions of the $J/\Psi$…

The rates for diffractive quarkonium plus prompt-photon associated production at the LHC are estimated. The theoretical framework considered in the J/Psi (or Upsilon) production associated with a direct photon at the hadron collider is the…

We investigate the low transverse momentum heavy quarkonium ($J/\psi$, $\Upsilon$) productions in the forward rapidity region of $pp$ and $pA$ collisions at the LHC as an important probe to the transverse momentum tomography of the gluons…

Charmonium states are expected to be considerably suppressed in the case of quark-gluon plasma formation in high-energy heavy-ion collisions. However, a robust identification of suppression patterns as signatures of a deconfined QCD medium…

In the limit of heavy quark mass, the production cross section and polarization of quarkonia can be calculated in perturbative QCD. We study the $p_\perp$-averaged production of charmonium states in $\pi N$ collisions at fixed target…

Based on the nonrelativistic QCD (NRQCD) factorization formalism, we investigate inclusive productions of two spin-triplet S-wave quarkonia pp->2J/psi+X, 2Upsilon+X, and J/psi+Upsilon+X at the CERN Large Hadron Collider. The total…

The production of charmonia in ultrarelativistic heavy-ion collisions is investigated including two sources. These are a primordial contribution coupled with various phases of dissociation, and a statistical coalescence of $c$ and $\bar{c}$…

Recent experiments have found spin alignment of $J/\psi$ with respect to event plane in heavy ion collisions, suggesting a medium effect that is spin dependent. We propose a possible mechanism with polarized dissociation from the motion of…

There is serious disagreement between the predictions of Non-Relativistic Quantum Chromodynamics (NRQCD) and the data on $J/\psi$ polarisation which has persisted for almost a quarter of a century. We find that if we account for the effect…

Measurements of the polarization of $\jp$ produced in pion-nucleus collisions are in disagreement with leading twist QCD prediction where $\jp$ is observed to have negligible polarization whereas theory predicts substantial polarization. We…

Polarization measurements are usually considered as the most difficult challenge for the QCD description of quarkonium production. In fact, global data fits for the determination of the non-perturbative parameters of bound-state formation…

Double $J/\psi$ production on the order of 20-30 pb has been observed by the NA3 collaboration. These $\psi \psi$ pairs, measured in $\pi^- N$ interactions at 150 and 280 GeV$/c$ and in $pN$ interactions at 400 GeV$/c$, carry a large…

We study the associated $J/{\psi}$ and direct photon production in the high-energy factorization, as it is formulated in the parton Reggeization approach, using two different models for the hadronization of a heavy quark-antiquark pair into…

The problem of quarkonium production in heavy ion collisions presents a set of unique theoretical challenges -- from the relevant production mechanism of $J/\psi$ and $\Upsilon$ to the relative significance of distinct cold and hot nuclear…

Prospects for quarkonium-production studies accessible during the upcoming high-luminosity phases of the CERN Large Hadron Collider operation after 2021 are reviewed. Current experimental and theoretical open issues in the field are…

We propose the measurement of $\chi_{cJ}$ polarizations at high energy hadron colliders to study heavy quarkonium production mechanism. We find that the color-singlet model in the $k_t$ factorization approach predicts very different…

Recently, several surprising experimental observations in the production of heavy quarkonium have been reported. In $e^+e^-$ annihilation at $\sqrt{s}=10.6$ GeV, Belle Collaboration finds that $J/\psi$ mesons are predominantly produced in…

We have performed a systematic study of $J/\psi$ and $\psi(2S)$ production in $p-p$ collisions at different LHC energies and at different rapidities using the leading order (LO) non-relativistic QCD (NRQCD) model of heavy quarkonium…

Within the framework of non-relativistic QCD (NRQCD) effective field theory, we study the leptoproduction of $J/{\psi}$ at next-to-leading order in perturbative QCD for both unpolarized and polarized electron-ion collisions. We demonstrate…