889 research outputs found

    Beam transmission efficiency between injector and target in the GANIL complex

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    http://accelconf.web.cern.ch/AccelConf/c84/papers/j22.pdfInternational audienceIn order to achieve a maximum transmission efficiency, efforts have been made in three directions : beam measurements, understanding of the physical phenomenon, tuning method. The characteristics of the beam extracted from the three cyclotrons have been measured. The ensuing optical effects are analysed. The tuning of the transport-lines, depending on the characteristics of the extracted beams and the required beam properties on the target, is described

    Parameters of the eigenellipsoid for separated sector cyclotron

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    http://accelconf.web.cern.ch/AccelConf/c89/papers/g1-09.pdfInternational audienc

    Six-dimensional beam matching for axial injection into a cyclotron

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    http://accelconf.web.cern.ch/AccelConf/c89/papers/g1-01.pdfInternational audienc

    Growth and optical properties of GaN/AlN quantum wells

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    We demonstrate the growth of GaN/AlN quantum well structures by plasma-assisted molecular-beam epitaxy by taking advantage of the surfactant effect of Ga. The GaN/AlN quantum wells show photoluminescence emission with photon energies in the range between 4.2 and 2.3 eV for well widths between 0.7 and 2.6 nm, respectively. An internal electric field strength of 9.2±1.09.2\pm 1.0 MV/cm is deduced from the dependence of the emission energy on the well width.Comment: Submitted to AP

    Leucemia linfocítica crónica y su respuesta al tratamiento en un perro

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    Se presenta un caso clínico de leucemia linfocítica crónica en una perra, describiendo el curso de la enfermedad, los métodos diagnósticos empleados y su respuesta al tratamiento quimioterápico.A case of chronic lymphocytic leukemia in a bitch is presented. In this paper we describe the evolution of the disease, the diagnosis protocol and the response to a chemotherapeutic treatment

    Level IV fugacity model by a continuous time control system.

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    A continuos time dynamic control system of the "Level IV Fugacity Model" is presented and applied to selected organic chemicals in evaluative environments system. In order to illustrate the numerical solution by this model a discretization is used to calculate the fugacity, concentration and fugacity settling time for a set of three insecticides applied in a hypothetical three compartmental environmental system. The model employs the fugacity concept and treats three bulk compartments: air, water and bottom sediment. Input to the model consists of a description of the environmental, the physical-chemical and reaction properties of the chemical, and emission rates. Expressions in matrix form are included for emissions, advections, reactions, and inter-phase transference. An algorithm to determine the values of the fugacities, concentrations and fugacity settling time is given

    AC-Conductivity Measure from Heat Production of Free Fermions in Disordered Media

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    We extend (Bru et al. in J Math Phys 56:051901-1-51, 2015) in order to study the linear response of free fermions on the lattice within a (independently and identically distributed) random potential to a macroscopic electric field that is time- and space-dependent. We obtain the notion of a macroscopic AC-conductivity measure which only results from the second principle of thermodynamics. The latter corresponds here to the positivity of the heat production for cyclic processes on equilibrium states. Its Fourier transform is a continuous bounded function which is naturally called (macroscopic) conductivity. We additionally derive Green–Kubo relations involving time-correlations of bosonic fields coming from current fluctuations in the system. This is reminiscent of non-commutative central limit theorems

    Macroscopic conductivity of free fermions in disordered media

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    We conclude our analysis of the linear response of charge transport in lattice systems of free fermions subjected to a random potential by deriving general mathematical properties of its conductivity at the macroscopic scale. The present paper belongs to a succession of studies on Ohm and Joule's laws from a thermodynamic viewpoint starting with [1-3]. We show, in particular, the existence and finiteness of the conductivity measure μΣ for macroscopic scales. Then we prove that, similar to the conductivity measure associated to Drude's model, μΣ converges in the weak*-topology to the trivial measure in the case of perfect insulators (strong disorder, complete localization), whereas in the limit of perfect conductors (absence of disorder) it converges to an atomic measure concentrated at frequency ν = 0. However, the AC-conductivity μΣ| ℝ\{0} does not vanish in general: We show that μΣ(ℝ\{0}) > 0, at least for large temperatures and a certain regime of small disorder
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