Papers by Cristiano Mariotto
In this article we review the mechanisms in several supersymmetric models for producing gluinos a... more In this article we review the mechanisms in several supersymmetric models for producing gluinos at the LHC and its potential for discovering them. We focus on the MSSM and its left-right extensions. We study in detail the strong sector of both models. Moreover, we obtain the total cross section and differential distributions. We also make an analysis of their uncertainties, such as the gluino and squark masses, which are related to the soft SUSY breaking parameters.
Proceedings of XXI International Workshop on Deep-Inelastic Scattering and Related Subjects — PoS(DIS 2013), Dec 5, 2013
In this contribution we investigate the influence of nuclear effects in hadroproduction of quarko... more 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.
Physical Review C, 2007
In this paper we estimate the influence of nonlinear gluon evolution in the production of prompt ... more In this paper we estimate the influence of nonlinear gluon evolution in the production of prompt photons at the LHC pp collider. We assume the validity of collinear factorization and consider the EHKQS parton distributions, which are solutions of the GLR-MQ evolution equations and describe quite well the DESY ep HERA data, as input in our calculations. We find that both single and double photon production are enhanced for low-pT photons and central rapidities, while this effect is absent for the high-pT photons. The implications of this effect for the Quark-Gluon Plasma searches and for the QCD background to Higgs are also discussed.
Physical Review C, 2011
In this article we investigate the influence of nuclear effects in the production of gluinos in n... more In this article 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 RpA = dσ(pA) dyd 2 p T /A dσ(pp) dyd 2 p T and RAA = dσ(AA) dyd 2 p T /A 2 dσ(pp) dyd 2 p T. We demonstrate that depending on the magnitude of the nuclear effects, the production of gluinos could be enhanced, compared to protonproton 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 SPS scenarios, corresponding to different soft SUSY breaking mechanisms, and find that the nuclear ratios are strongly dependent on that choice.
AIP Conference Proceedings, 2004
Production of bottomonium in hadronic colisions is studied in the framework of the soft colour ap... more Production of bottomonium in hadronic colisions is studied in the framework of the soft colour approach. We report some results for production of ϒ in the Tevatron and predictions for the future Large Hadron Collider (LHC).
AIP Conference Proceedings, 2002
Hard and soft QCD dynamics are both important in charmonium hadroproduction, as presented here th... more Hard and soft QCD dynamics are both important in charmonium hadroproduction, as presented here through a next-to-leading order QCD matrix element calculation combined with the colour evaporation model. Observed x F and p ⊥ distributions of J/ψ in hadroproduction are reproduced. Quite similar results can also be obtained with a Monte Carlo event generator where cc pairs are instead produced through leading order matrix elements and the parton shower approximation of higher order processes. The soft dynamics may alternatively be described by the soft colour interaction model. We also discuss the relative rates of different charmonium states and introduce an improved model for mapping the continuous cc mass spectrum on the physical charmonium resonances.
We discuss the relative rates of different charmonium states and introduce an improved model for ... more We discuss the relative rates of different charmonium states and introduce an improved model for mapping the continuous ccbar mass spectrum on the physical charmonium resonances.
In this article we review the mechanisms in several supersymmetric models for producing gluinos a... more In this article we review the mechanisms in several supersymmetric models for producing gluinos at the LHC and its potential for discovering them. We focus on the MSSM and its left-right extensions. We study in detail the strong sector of both models. Moreover, we obtain the total cross section and differential distributions. We also make an analysis of their uncertainties, such as the gluino and squark masses, which are related to the soft SUSY breaking parameters.
ABSTRACT In this work we investigate two cold matter effects in J/Ψ and Υ production in nuclear c... more ABSTRACT In this work we investigate two cold matter effects in J/Ψ and Υ 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, RpA = dσpA(J/Ψ,Υ)/Adσpp(J/Ψ,Υ) and RAA = dσAA(J/Ψ,Υ)/A2dσpp(J/Ψ,Υ).
In this contribution we investigate the influence of nuclear effects in hadroproduction of quarko... more 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.
Journal of High Energy Physics, 2002
Models with essential non-perturbative QCD dynamics for the production of charmonium are extrapol... more Models with essential non-perturbative QCD dynamics for the production of charmonium are extrapolated to give predictions of prompt J/ψ production at the LHC. Differences of up to an order of magnitude occurs, although the different models all describe the Tevatron data on high-p ⊥ charmonium. An important point is here the treatment of higher order perturbative QCD effects. We also discuss the large rate of prompt J/ψ from these models as a background to CP violation studies.
Physical Review D, 2013
In this paper we study the photon production in single and double diffractive processes consideri... more In this paper we study the 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 makes the experimental analysis of these observables feasible at LHC energies.
Physical Review D, 2012
In this work we investigate the photoproduction of massive gauge bosons, W ± and Z 0 , as part of... more 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 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 W W γ coupling.
Physical Review D, 2002
The diffractive photoproduction of vector mesons is usually described considering the two-gluon (... more The diffractive photoproduction of vector mesons is usually described considering the two-gluon (Pomeron) exchange, non-diagonal parton distributions and the contribution of the real part to the cross section. In this letter we analyze the diffractive photoproduction of the Υ at HERA using an alternative model, the Color Evaporation Model (CEM), where the cross section is simply determined by the boson-gluon cross section and an assumption for the production of the colorless state. We verify that, similarly to the J/Ψ case, the HERA data for this process can be well described by the CEM. Moreover, we propose the analyzes of the ratio R = σΥ/σ J/Ψ to discriminate between the distinct approaches.
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Papers by Cristiano Mariotto