In this paper we study the inclusive and diffractive double quarkonium production. Based on the nonrelativistic QCD (NRQCD) factorization formalism for the quarkonium production mechanism we estimate the rapidity and transverse momentum dependence of the cross section for the J/Ψ J/Ψ and ΥΥ production in diffractive processes at LHC energies. The contributions of the color-singlet and color-octet channels are estimated and predictions for the total cross sections in the kinematical regions of the LHC experiments are also presented. Our results demonstrate that the contribution of diffractive processes is not negligible and that its study can be useful to test the Resolved Pomeron model.

The double quarkonium production in single and double diffractive processes is investigated considering pp collisions at the Run 2 LHC energy. Using the nonrelativistic QCD factorization formalism for the quarkonium production and the resolved Pomeron model to describe the diffractive processes, we estimate the rapidity and transverse momentum dependencies of the cross sections for the J/Psi J/Psi and gamma gamma production. The contributions of the color-singlet and color-octet channels are estimated, and predictions for the total cross sections in the kinematical regions of the LHC experiments are also presented. Our results demonstrate that the double quarkonium production in diffractive processes is not negligible and that its study can be useful to test the underlying assumptions present in the description of the single and double diffractive processes.

In this paper we study the double J/ψ production in central diffractive processes considering the Resolved Pomeron model. Based on the nonrelativistic QCD (NRQCD) factorization formalism for the quarkonium production mechanism we estimate the rapidity and transverse momentum dependence of the cross section for the double J/ψ production in diffractive processes at LHC energies. The contributions of the color-singlet and color-octet channels are estimated and predictions for the total cross sections in the kinematical regions of the LHC experiments are also presented. Our results demonstrate that the contribution of central diffractive processes is not negligible and that its study can be useful to test the Resolved Pomeron model.

The high gluon density in the initial state of hadronic collisions at LHC energies implies that the probability of multiple parton interactions within one proton-proton collision increases. In particular, this motivates one to investigate the importance of Double Parton Scattering (DPS) processes at the LHC. In a DPS process one can have, from one proton-proton collision, two interacting partons coming from each colliding hadron. In this context, the relation between the double parton distribution functions (dPDF) and the usual parton distribution functions (PDF) is discussed, and some formulae for the DPS cross section are compared. Our results focus on the production of different final states related to two heavy quark-antiquark pairs. Those include [Formula: see text], which is called the golden channel of DPS, [Formula: see text] and [Formula: see text].

In this work we study the suppression of charged hadrons (pi(+/-), K-+/-, p and (p) over bar) in ultrarelativistic heavy ion (UHI) collisions, where the quark-gluon plasma (QGP) is believed to be produced. Jet energy loss in the QGP is the main explanation for jet quenching, which may suppress the number of hadrons produced while the jets traverse the dense and colorful medium created. By taking into account the energy loss of the partons traversing the medium and the nuclear shadowing of the parton distributions depending on the impact-parameter, we calculate the nuclear modification factor RAA for lead-lead collisions at the LHC. Finally, we estimate the opacity of the QGP in several centrality classes.

The high density of gluons in the initial state of hadronic collisions at LHC implies that the probability of multiple parton interactions within one proton-proton collision increases. In particular, the probability of having two or more hard interactions in a collision is not significantly suppressed with respect to the single interaction probability. In this contribution we study for the first time the production of prompt photons in double parton scattering processes. In particular, we estimate the rapidity distribution for the double Compton process, which leads to two photons plus two jets in the final state. Besides, we study the production of three and four photons in the final state, which are backgrounds to physics beyond the Standard Model.

In this paper we study the double J/ψ production in central diffractive processes considering the Resolved Pomeron model. Based on the nonrelativistic QCD (NRQCD) factorization formalism for the quarkonium production mechanism we estimate the rapidity and transverse momentum dependence of the cross section for the double J/ψ production in diffractive processes at LHC energies. The contributions of the color-singlet and color-octet channels are estimated and predictions for the total cross sections in the kinematical regions of the LHC experiments are also presented. Our results demonstrate that the contribution of central diffractive processes is not negligible and that its study can be useful to test the Resolved Pomeron model.

In this paper we study photon production in single and double diffractive processes considering the resolved pomeron model. We estimate the rapidity and transverse momentum dependence of the cross section for the diffractive double photon and photon + jet production. A comparison with the inclusive production is presented. We predict large values for the total cross sections, which make the experimental analysis of these observables feasible at LHC energies.

In this work we study the production of charged hadrons in ultrarelativistic heavy ion collisions. We quantify the medium effects by calculating the nuclear ratio RAA as a function of the transverse momentum of the produced hadron. The main ingredients are the shadowing of the nuclear parton distributions, the jet energy loss and the fragmentation functions modified by the hot and dense medium. Our results are focused on the interplay of the different effects, and results are compared with recent LHC data.

In this contribution we study for the first time the prompt photon production in single and double diffractive processes considering the resolved Pomeron model. We estimate the rapidity and transverse momentum dependence of the cross section for the production of two photons and of a photon and a jet. We show that these processes are sensitive to the pomeron structure. In contrast with the dijet and heavy quark production, which are dominated by gluon-gluon interactions, in prompt photon production, Compton like processes are dominant for single photon plus jet events. This gives a unique oportunity to constrain the quark distribution in the Pomeron. The results are obtained for the LHC energy.

In this work we investigate two cold matter effects in J/psi and gamma production in nuclear collisions at RHIC and LHC, namely the shadowing effect and nuclear absorption. We characterize these effects by estimating the rapidity dependence of some nuclear ratios in pA and AA collisions at RHIC and LHC, R-pA = d sigma(pA)(J/Psi, gamma)/Ad sigma(pp)(J/Psi,gamma) and R-AA = d sigma(AA)(J/Psi,gamma)/A(2)d sigma(pp)(J/Psi,gamma).

This review starts out with a brief history of the photino–gluino phenomenology. Next, it describes difficulties encountered in the construction of Feynman amplitudes when dealing with Majorana fermions and outlines a procedure that circumvents this difficulty by means of a prescription based on a well-defined fermion flow without explicit charge–conjugation matrices at the vertex equations. Finally, as an illustration, it calculates the cross section for the production of photinos and gluinos.

In this contribution we study the production of squarks. If squarks are found in proton-proton ( pp) collisions at the LHC, they might also be produced in collisions involving nuclei (pA and AA collisions). Here we investigate the influence of nuclear effects in the production of squarks in nuclear collisions at the LHC, and estimate the transverse momentum dependence of the nuclear ratios R-pA = d sigma(pA)/d(pT) / Ad sigma (pp)/d(pT) and R-AA = d sigma (AA)/d(pT) / A(2) d sigma (pp)/d(pT). We demonstrate that depending on the magnitude of the nuclear effects, the production of squarks could be enhanced or suppressed, compared to proton-proton collisions at same energies.

In this contribution we report on the investigation of the photoproduction of W and Z bosons in the planned electron-proton/nucleus collider, the LHeC. The production cross sections and the number of events are provided and theoretical uncertainties are discussed. We also analyze the sensitivity of the LHeC experiment to physics beyond Standard Model by studying the role played by anomalous WWgamma coupling in the presented process.

In this work we investigate the inclusive and exclusive photoproduction of dileptons, which is relevant for the physics programme to be studied in the proposed electron-proton collider, the LHeC. In the inclusive case, the process is sensitive to the parton distribution functions in the photon, whereas the exclusive channel is connected to the small-x QCD dynamics. For the latter, we investigate the role played by saturation physics at a very high energy scenario. The estimates for production cross sections and the number of events are presented.

In this work we investigate the photoproduction of massive gauge bosons, W-+/- and Z(0), as part of relevant physics topics to be studied in the proposed electron-proton collider, the Deep Inelastic Electron-Nucleon Scattering at the LHC (LHeC). The estimates for production cross sections and the number of events are presented. In addition, motivated by the intensive studies to test the deviations from the Standard Model at present and future colliders, we discuss the W-+/- asymmetries and perform an analysis on the role played by anomalous WW gamma coupling.

In this paper, we investigate the influence of nuclear effects in the production of gluinos in nuclear collisions at the Large Hadron Collider, and estimate the transverse momentum dependence of the nuclear ratios R-pA = d sigma(pA)/dyd(2)pT / A d sigma(pp)/dyd(2)pT and R-AA = d sigma(AA)/dyd(2)pT / A(2) d sigma(pp)/dyd(2)pT. We demonstrate that depending on the magnitude of the nuclear effects, the production of gluinos could be enhanced, compared to proton-proton collisions. The study of these observables can be useful to determine the magnitude of the shadowing and antishadowing effects in the nuclear gluon distribution. Moreover, we test different snowmass points and slopes scenarios, corresponding to different soft, supersymmetry breaking mechanisms, and find that the nuclear ratios are strongly dependent on that choice.

In this work we investigate the influence of nuclear effects in the production of gluinos in nuclear collisions at the LHC, and estimate the transverse momentum dependence of the nuclear ratios R-pA = 1d(2)sigma(p(A))/d eta dp(T) / Ad(2)sigma(pp)/d eta dp(T) and R-AA = d(2)sigma(AA)/d eta dp(T)/A(2)d(2)sigma(pp)/d eta dp(T). We demonstrate that depending on the magnitude of the nuclear effects, the production of gluinos could be enhanced or supressed, compared to proton-proton collisions, which affect the detectability of gluinos in the pA and AA modes at the LHC.

In this contribution we investigate the influence of nuclear effects in hadroproduction of quarkonium associated with a photon. At high energies, such processes provide a probe of the QCD dynamics as it is dependent on the nuclear gluon distribution, and could be usefull in constraining the behavior of the nuclear gluon distribution in proton-nucleus and nucleus-nucleus collisions. Here we study the influence of the shadowing effect, in the production of J/Psi+gamma at the LHC and estimate the PT dependence of the nuclear modification factors. The theoretical framework considered for J/Psi+gamma production is the non-relativistic QCD (NRQCD) factorization formalism.

Quarkonium hadroproduction in association with a photon at high energies provides a probe of the dynamics of the strong interactions as it is dependent on the nuclear gluon distribution. Therefore, it could be used to constrain the behavior of the nuclear gluon distribution in proton–nucleus and nucleus–nucleus collisions. Such processes are useful to single out the magnitude of the shadowing/antishadowing effects in the nuclear parton densities. In this work we investigate the influence of nuclear effects in the production of J/ψ+γ and ϒ+γ and estimate the transverse momentum dependence of the nuclear modification factors. The theoretical framework considered in the J/ψ (ϒ) production associated with a direct photon at the hadron collider is the non-relativistic QCD (NRQCD) factorization formalism.