ηc\eta_c production in photon - induced interactions at the LHC

In this paper we investigate the $\eta_c$ production by photon - photon and photon - hadron interactions in $pp$ and $pA$ collisions at the LHC energies. The inclusive and diffractive contributions for the $\eta_c$ photoproduction are estimated using the nonrelativistic quantum chromodynamics (NRQCD) formalism. We estimate the rapidity and transverse momentum distributions for the $\eta_c$ photoproduction in hadronic collisions at the LHC and present our estimate for the total cross sections at the Run 2 energies. A comparison with the predictions for the exclusive $\eta_c$ photoproduction, which is a direct probe of the Odderon, also is presented.Comment: 9 pages, 5 figures, 1 table. arXiv admin note: text overlap with arXiv:1708.0149

Probing the X(4350)X(4350) in γγ\gamma \gamma interactions at the LHC

The production of $X(4350)$ in the $\gamma \gamma$ interactions that occur in proton-proton, proton-nucleus and nucleus-nucleus collisions at the CERN Large Hadron Collider (LHC) is investigated and predictions for the kinematical ranges probed by the ALICE and LHCb Collaborations are presented. We focus on the $\gamma \gamma \rightarrow \phi J/\Psi$ process, which have been measured by the Belle Collaboration, and present parameter free predictions for the total cross sections at the LHC energies. Our results demonstrate that the experimental study of this process is feasible and can be used to confirm or not the existence of the $X(4350)$ state. Finally, for completeness, we present predictions for the production of the $X(3915)$ state in the $\gamma \gamma \rightarrow \omega J/\Psi$ process and show that this exotic state can also be probed in $\gamma \gamma$ interactions at the LHC.Comment: 5 pages, 2 figures, 2 table

Diffractive quarkonium photoproduction in pppp and pApA collisions at the LHC: Predictions of the Resolved Pomeron model for the Run 2 energies

The inclusive diffractive quarkonium photoproduction in $pp$ and $pA$ collisions is investigated considering the Resolved Pomeron Model to describe the diffractive interaction. We estimate the rapidity and transverse momentum distributions for the $J/\Psi$, $\Psi(2S)$ and $\Upsilon$ photoproduction in hadronic collisions at the LHC and present our estimate for the total cross sections at the Run 2 energies. A comparison with the predictions associated to the exclusive production also is presented. Our results indicate that the inclusive diffractive production is a factor $\gtrsim 10$ smaller than the exclusive one in the kinematical range probed by the LHC.Comment: 9 pages, 5 figures, 1 table. Improved version to be published in Physical Review D. Numerical bug corrected. All figures were replaced. One new figure and the NRQCD and CEM predictions for the quarkonium production have been include

Double vector meson production in γγ\gamma \gamma interactions at hadronic colliders

In this paper we revisit the double vector meson production in $\gamma \gamma$ interactions at heavy ion collisions and present, by the first time, predictions for the $\rho\rho$ and $J/\Psi J/\Psi$ production in proton -- nucleus and proton -- proton collisions. In order to obtain realistic predictions for rapidity distributions and total cross sections for the double vector production in ultra peripheral hadronic collisions we take into account of the description of $\gamma \gamma \rightarrow VV$ cross section at low energies as well as its behaviour at large energies, associated to the gluonic interaction between the color dipoles. Our results demonstrate that the double $\rho$ production is dominated by the low energy behaviour of the $\gamma \gamma \rightarrow VV$ cross section. In contrast, for the double $J/\Psi$ production, the contribution associated to the description of the QCD dynamics at high energies contributes significantly, mainly in $pp$ collisions. Predictions for the RHIC, LHC, FCC and CEPC - SPPC energies are shown.Comment: 9 pages, 5 figures, 2 tables. arXiv admin note: text overlap with arXiv:1504.0441

Light quark mass differences in the π0−η−η′\pi^0 - \eta - \eta' system

A generalized 3 flavor Nambu-Jona--Lasinio Lagrangian including the explicit chiral symmetry breaking interactions which contribute at the same order in the large $1/N_c$ counting as the $U_A(1)$ 't Hooft flavor determinant is considered to obtain the mixing angles in the $\pi^0-\eta-\eta'$ system and related current quark mass ratios in close agreement with phenomenological values. At the same time an accurate ordering and magnitude of the splitting of states in the low lying pseudoscalar nonet is obtained.Comment: 6 pages, 4 tables, presented at the workshop "Excited QCD 2016", 05-12 March 2016, Costa da Caparica, Portugal. Submitted to Acta Phys. Pol.

Double vector meson production in the International Linear Collider

In this paper we study double vector meson production in $\gamma \gamma$ interactions at high energies and, using the color dipole picture, estimate the main observables which can be probed at the International Linear Collider (ILC). The total $\gamma (Q_1^2) + \gamma (Q_2^2) \rightarrow V_1 + V_2$ cross-sections for $V_i = \rho$, $\phi$, $J/\psi$ and $\Upsilon$ are computed and the energy and virtuality dependencies are studied in detail. Our results demonstrate that the experimental analysis of this process is feasible at the ILC and it can be useful to constrain the QCD dynamics at high energies.Comment: 11 pages, 8 figure