Related papers: Probing Gluons in Nuclei: the Case of $\eta'$
Using the recently proposed $gg\eta'$ effective vertex, we investigate the production of $\eta'$ from gluon fusion in polarized pp collisions. We show that by measuring $A_{LL}$ in $\eta'$ production, one can extract the polarized gluon…
We study the production of $\eta'$ from hadronizing thermal gluons using recently proposed $\eta'-g-g$ effective vertex. The $\eta'$ yield is found to be sensitive to the initial condition. At RHIC and LHC, the enhancement is large enough…
We compute the inclusive differential cross section production of the pseudo-scalar meson eta' in high-energy proton-proton (pp) and proton-nucleus (pA) collisions. We use an effective coupling between gluons and eta' meson to derive a…
We study gluon production in high energy proton-nucleus collisions in the semi-classical framework of the Color Glass Condensate. We develop a general formalism to compute gluon fields in covariant gauge to lowest order in the classical…
We demonstrate the recently proposed nucleon energy-energy correlator (nucleon EEC) $f_{\rm EEC}(x,\theta)$ can unveil the gluon saturation in the small-$x$ regime in $eA$ collisions. The novelty of this probe is that it is fully inclusive…
A new experiment is proposed with the aim to study eta-mesic nuclei and low-energy interactions of eta with nuclei. Two decay modes of eta produced by a photon beam inside a nucleus will be observed, namely a collisional decay \eta N \to…
Heavy-ion collisions at the BNL-RHIC collider can probe whether gluon saturation effects in nuclei at small x have set in, or whether leading-twist perturbative estimates of particle production are still applicable. I discuss that soon to…
Inclusive production of $J/\psi$ mesons, especially at forward rapidities, is an important probe of small-x gluons in protons and nuclei. In this paper we re-evaluate the production cross sections in the Color Glass Condensate framework,…
The production of $\eta'$ mesons in the reactions $pp\to pp\eta'$ and $pn\to pn\eta' $ at threshold-near energies is analyzed within a covariant effective meson-nucleon theory. The description of cross section and angular distributions of…
We propose to measure the gluon distribution function Delta G(eta) at eta < 0.2 via pseudo jet production in polarized fixed target lepton nucleon scattering at typical lepton beam energies of 200 GeV. The measurement of the spin-asymmetry…
The forthcoming LHC measurement of hadron multiplicity in proton-nucleus collisions is a crucial test of the k_t factorization and gluon saturation based models. Here, we provide quantitative predictions for the pseudorapidity distribution…
I discuss exclusive production of the $\eta'$ meson in the $pp \to p\eta'p$ reaction far from the threshold. The contribution of diffractive component as well as that for $\gamma^* \gamma^* \to \eta'$ fusion are calculated. In the first…
We review the present understanding of etaprime and eta meson physics and these mesons as a probe of gluon dynamics in low-energy QCD. Recent highlights include the production mechanism of eta and etaprime mesons in proton-nucleon…
It is reported on a leading-twist analysis of the eta - photon and eta' - photon transition form factors. The analysis allows for an estimate of the lowest Gegenbauer coefficients of the quark and gluon distribution amplitudes.
At small x, the gluon distribution dominates the nuclear wave function. The increase needs to be tamed in avoid violating unitarity constraints. The most efficient way to study this in colliders is through e+A collisions as the nucleus is…
Starting from a recent model of the eta'N interaction, we evaluate the eta'-nucleus optical potential, including the contribution of lowest order in density, t rho/2m_eta', together with the second order terms accounting for eta' absorption…
We study open heavy flavor meson production in proton-nucleus (pA) collisions at RHIC and LHC energies within the Color Glass Condensate framework. We use the unintegrated gluon distribution at small Bjorken's x in the proton obtained by…
We discuss the sensitivity of eta and eta' photoproduction near threshold to the gluonic OZI breaking parameters in the U_A(1)-extended effective chiral Lagrangian for low-energy QCD. Our coupled-channels analysis hints at a strong…
The interaction of spatially small dipoles with nucleons, nuclei is calculated in the DGLAP approximation at the top of HERA energies and found to be close to the $S$-channel unitarity limit in the case of the color octet dipoles. The DGLAP…
We have studied how lepton pairs from decays of heavy-flavoured mesons produced in p$A$ collisions can be used to determine the modifications of the gluon distribution in the nucleus. Since heavy quark production is dominated by the $gg$…