6,615 research outputs found
Highlights in particle physics
proceedings pour la Conf.International audienc
Electroweak Precision Tests
International audienceThis lecture deals with the consistency check of the Standard Model (SM) hypothesis driven by the electroweak precision measurements performed at the Z boson pole (LEP and SLC experiments) and at high energy hadronic machines (Tevatron experiments). Together with the Cabibbo-Kobayashi-Maskawa (CKM) matrix parameters t, the Z-pole observables consistency check is a pillar of the SM. Following A. Korshin's lecture on SM, we will rst describe the free parameters of the SM and introduce the necessity to go beyond the Born approximation. We will hence review the relevant radiative corrections which must be considered as far as the processes at the Z pole are concerned and de ne which observables can be used to constrain the yet unknown parameters of the SM in the gauge sector. Eventually, we will interpret the global quantum consistency check in terms of the top quark and Higgs masses constraint. The comparison of the predicted and measured top quark mass is a tremendous success of the SM. The prediction of the Higgs mass is driving to a large extent the physics case of the LHC machine
CKM Fits: the Standard Model and the New Physics
International audienc
Simulation of ultrashort heat pulses on vitreous thin plates-application to the determination of dynamic constants
Date du colloque : 09/2010International audienc
Molecular dynamics simulation of phase transitions in crystalline lead (II) fluoride
Using classical molecular dynamics applied to crystalline PbF2, we have simulated transitions between cubic and orthorhombic phases and reciprocally. These transitions were induced by pressure and temperature treatments. The orthorhombic phase was evidenced by analysis of different distribution functions and XRD spectra drawn from the ions positions in the simulated samples. (C) 2014 Elsevier B.V. All rights reserved
Molecular dynamics simulation of Eu3+ in aqueous solution comparison with experimental luminescence spectra
Using molecular dynamics simulations, we have studied the environment of Eu3+ salts in aqueous solution. In the case of hydration number of 8, the symmetry of the first hydration shell is found to be very close to the D4d. We have therefrom calculated the ligand field parameters according to the point charge model. The luminescence spectra were reconstructed from this set of computed Bkq, and finally compared with experimental spectra
Numerical Simulations of the Structure and Spectroscopic Properties of Rare-Earth Doped Glasses
A review of the research that has been devoted to the simulation of the structure and spectroscopic properties of rare-earth doped glasses is presented. Since the seminal papers of Brawer and Weber who have applied Monte-Carlo or molecular dynamics techniques, some other very important results have been reported concerning the local structure of the dopants. As a result, crystal field models have been applied and several pecularities of the optical spectra of rare earth ions in glasses have been understood
Molecular dynamics simulations of rare-earth-doped glasses
In the recent years the use of the molecular dynamics technique has become very common in the study of glass. The purpose of the present paper is to focus on recent advancements on the use of this method to investigate rare-earth-doped glasses. We report an overview of the use of simulations to study their specific structural features and luminescence properties
Phonon-Assisted Photoluminescence in a Spherical Nanocrystal
Using the matrix density in the representation of path integrals for an electron, the multiphoton nonlinear absorption light coefficient in the second order of interaction energy with polar optical phonons is derived. This coefficient describes any electron interaction mechanism with phonons. From the interaction mechanism, the main role is played by dimensional resonance when the electron continuously absorbs energy from the field as a result of synchronizing its oscillation with the field. This dimensional resonance is possible when the frequency characterizing the laser field is a multiple of the phonon frequency. Whether a photon is absorbed or emitted, the initial level from where the transition occurs defines the temperature dependence. The absorption spectrum has the form of stripes whose intensity depends on the resonance character. The most pronounced absorption is at the triple resonance, where values of radiation and oscillatory and optical phonon frequencies are equal
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