Percolation approach to quark gluon plasma in high energy pp collisions

We apply continuum percolation to proton-proton collisions and look for the possible threshold to phase transition from confined nuclear matter to quark gluon plasma. Making the assumption that J/Psi suppression is a good signal to the transition, we discuss this phenomenon for pp collisions, in the framework of a dual model with strings.Comment: 8 pages, 3 figure

Six-dimensional weak-strong simulations of head-on beam-beam compensation in RHIC

To compensate the large beam-beam tune spread and beam-beam resonance driving terms in the polarized proton operation in the Relativistic Heavy Ion Collider (RHIC), we will introduce a low-energy DC electron beam into each ring to collide head-on with the opposing proton beam. The device to provide the electron beam is called an electron lens. In this article, using a 6-D weak-strong-beam-beam interaction simulation model, we investigate the effects of head-on beam-beam compensation with electron lenses on the proton beam dynamics in the RHIC 250 GeV polarized proton operation. This article is abridged from the published article [1].Comment: 5 pages, contribution to the ICFA Mini-Workshop on Beam-Beam Effects in Hadron Colliders, CERN, Geneva, Switzerland, 18-22 Mar 201

Lagrangian formulation for noncommutative nonlinear systems

In this work we use the well known formalism developed by Faddeev and Jackiw to introduce noncommutativity within two nonlinear systems, the SU(2) Skyrme and O(3) nonlinear sigma models. The final result is the Lagrangian formulations for the noncommutative versions of both models. The possibility of obtaining different noncommutative versions for these nonlinear systems is demonstrated.Comment: 8 pages. Revex 4.

Clan structure analysis and new physics signals in pp collisions at LHC

The study of possible new physics signals in global event properties in pp collisions in full phase space and in rapidity intervals accessible at LHC is presented. The main characteristic is the presence of an elbow structure in final charged particle MD's in addition to the shoulder observed at lower c.m. energies.Comment: 9 pages, talk given at Focus on Multiplicity (Bari, Italy, June 2004

Effect of Charged Scalar Loops on Photonic Decays of a Fermiophobic Higgs

Higgs bosons with very suppressed couplings to fermions ("Fermiophobic Higgs bosons", h_f) can decay to two photons (\gamma\gamma) with a branching ratio significantly larger than that expected for the Standard Model Higgs boson for m_{h_f}<150 GeV. Such a particle would give a clear signal at the LHC and can arise in the Two Higgs Doublet Model (type I) in which h_f -> \gamma\gamma is mediated by W^+ and charged Higgs boson (H^+) loops. We show that the H^+ loops can cause both constructive and destructive contributions with a magnitude considerably larger than the anticipated precision in the measurement of the photonic decay channel at future hadron and lepton colliders.Comment: 18 pages, 5 figures, clarifications added, one reference added, accepted by Physical Review

Metodologia de determinação do pH da temperatura da cama de aviário em tempo real.

Projeto: 03.07.09.049

Open string with a background B-field as the first order mechanics, noncommutativity and soldering formalism

To study noncommutativity properties of the open string with constant B-field we construct a mechanical action which reproduces classical dynamics of the string sector under consideration. It allows one to apply the Dirac quantization procedure for constrained systems in a direct and unambiguous way. The mechanical action turns out to be the first order system without taking the strong field limit $B\longrightarrow\infty$. In particular, it is true for zero mode of the string coordinate which means that the noncommutativity is intrinsic property of this mechanical system. We describe the arbitrariness in the relation existent between the mechanical and the string variables and show that noncommutativity of the string variables on the boundary can be removed. It is in correspondence with the result of Seiberg and Witten on relation among noncommutative and ordinary Yang-Mills theories. The recently developed soldering formalism helps us to establish a connection between the original open string action and the Polyakov action.Comment: Revtex4, 8 pages. To appear in Physical Review

B Physics at the Z0 Resonance

B physics results from e+ e- annihilation at the Z0 resonance are reviewed. A vast program is summarised, including the study of B+, B0d, B0s and b baryon lifetimes, the time dependence of B0d and B0s oscillations, the width difference in the B0s system, and the measurements of the magnitudes of the CKM matrix elements Vcb and Vub.Comment: 17 pages, 8 figures, presented at the UK Phenomenology Workshop on Heavy Flavour and CP Violation, 17-22 September 200

Enriquecimento ambiental de gaiolas como estratégia prática para incrementar o bem-estar e a produção de ovos de poedeiras pesadas.

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