From sine-Gordon to vacuumless systems in flat and curved spacetimes

In this work we start from the Higgs prototype model to introduce a new model, which makes a smooth transition between systems with well located minima and systems that support no minima at all. We implement this possibility using the deformation procedure, which allows the obtention of a sine-Gordon-like model, controlled by a real parameter that gives rise to a family of models, reproducing the sine-Gordon and the so-called vacuumless models. We also study the thick brane scenarios associated with these models and investigate their stability and renormalization group flow. In particular, one shows how gravity can change from the 5-dimensional warped geometry with a single extra dimension of infinite extent to the conventional 5-dimensional Minkowski geometry.Comment: 11 pages, 12 figures. Version to appear in EPJ

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

Counterions at charge-modulated substrates

We consider counterions in the presence of a single planar surface with a spatially inhomogeneous charge distribution using Monte-Carlo simulations and strong-coupling theory. For high surface charges, multivalent counterions, or pronounced substrate charge modulation the counterions are laterally correlated with the surface charges and their density profile deviates strongly from the limit of a smeared-out substrate charge distribution, in particular exhibiting a much increased laterally averaged density at the surface.Comment: 7 page

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