Related papers: J/psi polarization from fixed-target to collider e…
In these proceedings, measurements of J/psi polarization in p+p collisions at 200 and 500 GeV via the dielectron decay channel at mid-rapidity with the STAR experiment are discussed. At 200 GeV the polarization parameter,…
We have measured the polarizations of $\jpsi$ and $\psiprime$ mesons as functions of their transverse momentum $\pt$ when they are produced promptly in the rapidity range $|y|<0.6$ with $\pt \geq 5 \pgev$. The analysis is performed using a…
Understanding the polarization property of $J/\psi$ is critical to constrain its production mechanism. In addition, the polarization of $J/\psi$ can reveal the impact of strong electromagnetic and vorticity fields in relativistic heavy ion…
We report on a polarization measurement of inclusive $J/\psi$ mesons in the di-electron decay channel at mid-rapidity at 2 $<p_{T}<$ 6 GeV/$c$ in $p+p$ collisions at $\sqrt{s}$ = 200 GeV. Data were taken with the STAR detector at RHIC. The…
With nonrelativistic QCD factorization, we present a full next-to-leading order computation of the polarization observable for $J/psi$ production at hadron colliders including all important Fock states, i.e. $^3S_1[1,8]$, $^1S_0[8]$, and…
We study the polarization of inclusive J/$\psi$ produced in Pb$-$Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV at the LHC in the dimuon channel, via the measurement of the angular distribution of its decay products. We perform the study in…
We report the measurement of the transverse momentum dependence of inclusive J/psi polarization in p+p collisions at sqrt(s)=200 GeV performed by the PHENIX Experiment at RHIC. The polarization is studied in the helicity, Gottfried-Jackson,…
In e^+e^- annihilation at \sqrt{s}=10.6 GeV Belle Collaboration found, that J/psi mesons are predominantly produced in association with an extra \bar{c}c pair. The possible mechanisms of J/psi production are discussed and the probability of…
We investigate the J/psi polarization in photoproduction at the Hadron Electron Ring Accelerator(HERA) up to the next-to-leading order of QCD. The results show that the transverse momentum p_t and energy fraction z distributions of J/psi…
We consider the J/psi photo-production data collected at HERA in the light of next-to-leading order predictions for the color-singlet yield and polarization. We find that, while the shapes of inclusive distributions in the transverse…
We report on new measurements of inclusive J/$\psi$ polarization at mid-rapidity in p+p collisions at $\sqrt{s}$ = 200 GeV by the STAR experiment at RHIC. The polarization parameters, $\lambda_\theta$, $\lambda_\phi$, and…
The first measurement of inclusive J/psi polarization at mid-rapidity (|y^{J/psi}| < 0.8) in 200 GeV Ru+Ru and Zr+Zr collisions at sqrt(s_NN) = 200 GeV with the STAR experiment at RHIC is presented. J/psi mesons are reconstructed through…
We report on the measurement of the inclusive J/$\psi$ polarization parameters in pp collisions at a center of mass energy $\sqrt{s} = 8$ TeV with the ALICE detector at the LHC. The analysis is based on a data sample corresponding to an…
In this paper, J/$\psi$ polarization at mid-rapidity in $p+p$ collisions at $\sqrt{s}$ = 200 GeV measured in the STAR experiment at RHIC is reported. J/$\psi$ production is analyzed via the dielectron decay channel. J/$\psi$ polarization is…
An angular analysis of the decay $J/\psi \rightarrow \mu^{+} \mu^{-}$ is performed to measure the polarization of prompt $J/\psi$ mesons produced in $pp$ collisions at $\sqrt{s}=7\; \mathrm{TeV}$. The dataset corresponds to an integrated…
The polarizations of prompt J/psi and psi(2S) mesons are measured in proton-proton collisions at sqrt(s) = 7 TeV, using a dimuon data sample collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.9…
We present measurements of the polarization of the $ J/\psi $ produced in 800-GeV proton interactions with a copper target. Polarization of the $ J/\psi $ is sensitive to the $ c \bar{c} $ production and hadronization processes. A…
We calculate the production and polarization of direct $J/\psi$ in the improved color evaporation model in $e+p$ photoproduction. We present the production as functions of transverse momentun, mass of the hadronic final state, and…
Based on the non-relativistic quantum chromodynamics factorization formalism, the polarization parameters $\lambda_{\theta\phi}$ and $\lambda_{\phi}$ of $J/\psi$ hadroproduction are analyzed in helicity frame and calculated at QCD…
The polarizations of prompt and non-prompt J$/\psi$ and $\psi$(2S) mesons are measured in proton-proton collisions at $\sqrt{s}$ = 13 TeV, using data samples collected by the CMS experiment in 2017 and 2018, corresponding to a total…