18.1k citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- University of LisbonPT1.3k papers
- Universidade Técnica de LisboaPT388 papers
- Centre National de la Recherche ScientifiqueFR326 papers
- Instituto de Plasmas e Fusão NuclearPT209 papers
- European Organization for Nuclear ResearchCH202 papers
- Centro de Física Teórica de Partículas201 papers
- Instituto Politécnico de LisboaPT190 papers
- Instituto de TelecomunicaçõesPT175 papers
- Universitat de ValènciaES175 papers
- Institut National de Physique Nucléaire et de Physique des ParticulesFR143 papers
- Centro de Astrofísica e GravitaçãoPT133 papers
- LIP - Laboratory of Instrumentation and Experimental Particle PhysicsPT133 papers
20 papers · 2 filters
Percolation approach to phase transitions in high energy nuclear collisions
A. Rodrigues, R. Ugoccioni, J. Dias de Deus
We study continuum percolation in nuclear collisions for the realistic case in which the nuclear matter distribution is not uniform over the collision volume, and show that the per…
Note on Shadowing and Diffraction in Deep-Inelastic Lepton Scattering
G. Piller, L. Ferreira, W. Weise
We discuss the close relation between shadowing in deep-inelastic lepton-nucleus scattering and diffractive photo- and leptoproduction of hadrons from free nucleons. We show that t…
Yukawa coupling corrections to the decay
Andrew Akeroyd, Abdesslam Arhrib, El-Mokhtar Naimi
We compute the fermionic radiative contributions to the decay in the framework of models with two Higgs doublets (2HDM), for the case of an on-shell and off-…
Degenerate and Quasi Degenerate Majorana Neutrinos
G. C. Branco, M. N. Rebelo, J. I. Silva-Marcos
We study mixing and CP violation of three left-handed Majorana neutrinos in the limit of exactly degenerate masses, identify the weak-basis invariant relevant for CP violation and…
Quark Mass Hierarchy, FCNC and CP violation in a Seesaw model
Y. Kiyo, T. Morozumi, P. Parada +2
The seesaw model of quark masses is studied systematically, focusing on its developments. A framework allowing the top quark mass to be of the order of the electroweak symmetry bre…
Solar Magnetic Field Profiles and SuperKamiokande Data
Joao Pulido
The distortion of the energy spectrum of recoil electrons in SuperKamiokande resulting from several solar magnetic field profiles that are consistent with data and standard solar m…
Vector Boson decays of the Higgs Boson
J. C. Romao, S. Andringa
We derive the width of the Higgs boson into vector bosons. General formulas are derived both for the on-shell decay H -> VV as well for the off-shell decays, H -> V^* V and H -> V^…
Confinement and chiral symmetry breaking in heavy-light quark systems
P. Bicudo, N. Brambilla, E. Ribeiro +1
Assuming a Gaussian approximation for the QCD gluodynamics, all the nonperturbative physics can be encoded into two parameters: the gluon correlation length and the gluon con…
Comment on ``Indirect CP violation in the B-system''
L. Lavoura
In a recent paper, Banuls and Bernabeu have claimed the existence of a new form of indirect CP violation which would have its most prominent manifestation in the - s…
The Anomalous Magnetic Moment of Quarks
Pedro J. de A. Bicudo, J. Emilio F. T. Ribeiro, Rui Fernandes
In the case of massless current quarks we find that the breaking of chiral symmetry usually triggers the generation of an anomalous magnetic moment for the quarks. We show that the…
Flavour symmetry of mesonic decay couplings
Eef van Beveren, George Rupp
We present flavour-symmetric results for the couplings of quark-antiquark systems to meson-meson channels in the harmonic-oscillator expansion. We tabulate their values for all pos…
Comment on ``Understanding the scalar meson quark-antiquark nonet''
Eef van Beveren, George Rupp
It is shown that the incomplete scalar meson nonets found by Toernqvist (T) and Toernqvist and Roos (TR), employing a new version of the Helsinki unitarised quark model, should in…
Electroweak Baryogenesis in the Presence of an Isosinglet Quark
G. C. Branco, D. Delepine, D. Emmanuel-Costa +1
We consider the possibility of electroweak baryogenesis in a simple extension of the standard model with an extra singlet complex scalar and a vector-like down quark. We show that…
High Energy Neutrino, Photon and Cosmic Ray Fluxes from VHS Cosmic Strings
Ubi F. Wichoski, Jane H. MacGibbon, Robert H. Brandenberger
Decaying topological defects, in particular cosmic strings, can produce a significant flux of high energy neutrinos, photons and cosmic rays. According to the prevailing understand…
Asymmetries in Heavy Meson Production from Light Quark Fragmentation
J. Dias de Deus, F. O. Duraes
We discuss the possibility of the asymmetry in production, from beams, being a direct consequence of the properties of the light quark fragmentation function into h…
Absorption and J/psi Suppression in Heavy Ion Collisions
J. Dias de Deus, J. Seixas
We discuss the J/psi suppression in the framework of multiple collision models. From the analysis of the Pb-Pb NA50 data we conclude that the strength of the absorption has increas…
Leading Particle Effect in the Elasticity Distribution
F. O. Durães, F. S. Navarra, G. Wilk
Recent DESY-HERA data on elasticity distribution show that it emerges mostly as a fast particle. Interpreting photoproduction as a collision between a pre-formed charmed hadr…
Energy Dependence of Solar Neutrino Suppression and Bounds on the Neutrino Magnetic Moment
Joao Pulido, Ana M. Mourao
An analysis of neutrino electron scattering as applied to the SuperKamiokande solar neutrino experiment with the data from the Homestake experiment leads to an upper bound on the n…
Quasi degenerate Neutrino Masses with Universal Strength Yukawa Couplings
G. C. Branco, M. N. Rebelo, J. I. Silva-Marcos
A simple ansatz is proposed for neutrino and charged lepton mass matrices, within the framework of universal strength for Yukawa couplings. In this framework all Yukawa couplings h…
Gauge and Yukawa Unification with Broken R-Parity
Marco A. Diaz, J. Ferrandis, Jorge C. Romao +1
We study gauge and Yukawa coupling unification in the simplest extension of the Minimal Supersymmetric Standard Model (MSSM) which incorporates R-Parity violation through a bilinea…