1,045 research outputs found

    Light Quark Masses in Multi-Quark Interactions

    Get PDF
    We suggest and discuss in detail a multi-quark three flavor Lagrangian of the Nambu -- Jona-Lasinio type, which includes a set of effective interactions proportional to the current quark masses. It is shown that within the dynamical chiral symmetry breaking regime, the masses of the pseudo Goldstone bosons and their chiral partners, members of the low lying scalar nonet, are in perfect agreement with current phenomenological expectations. The role of the new interactions is analyzed.Comment: 8 pages, published versio

    Giant thermoemf in multiterminal superconductor/normal metal mesoscopic structures

    Full text link
    We considered a mesoscopic superconductor/normal metal (S/N) structure in which the N reservoirs are maintained at different temperatures. It is shown that in the absence of current between the N reservoirs a voltage difference VTV_{T} arises between the superconducting and normal conductors. The voltage VTV_{T} oscillates with increasing phase difference ϕ\phi between the superconductors, and its magnitude does not depend on the small parameter (T/ϵF).(T/\epsilon_{F}).Comment: Resubmited, some changes to Text and Figure

    On the Origin of the Enhancementof CP-violating Charge Asymmetries in K3πK \rightarrow 3\pi Decays Predicted from Chiral Theory

    Full text link
    We present an analysis of the enhancement of CP-violating charge asymmetries in K3πK \rightarrow 3\pi decays. Calculations of decay amplitudes are performed on the basis of bosonized strong and weak Lagrangians derived from QCD-motivated quark Lagrangians. We show that the interplay of fourth-order contributions of chiral Lagrangians for strong interactions and penguin operators in weak interactions significantly enhances the charge asymmetries.Comment: DESY 92-106, 15

    Coherent Charge Transport in Metallic Proximity Structures

    Full text link
    We develop a detailed microscopic analysis of electron transport in normal diffusive conductors in the presence of proximity induced superconducting correlation. We calculated the linear conductance of the system, the profile of the electric field and the densities of states. In the case of transparent metallic boundaries the temperature dependent conductance has a non-monotoneous ``reentrant'' structure. We argue that this behavior is due to nonequilibrium effects occuring in the normal metal in the presence of both superconducting correlations and the electric field there. Low transparent tunnel barriers suppress the nonequilibrium effects and destroy the reentrant behavior of the conductance. If the wire contains a loop, the conductance shows Aharonov-Bohm oscillations with the period Φ0=h/2e\Phi_0=h/2e as a function of the magnetic flux Φ\Phi inside the loop. The amplitude of these oscillations also demonstrates the reentrant behavior vanishing at T=0T=0 and decaying as 1/T1/T at relatively large temperatures. The latter behavior is due to low energy correlated electrons which penetrate deep into the normal metal and ``feel'' the effect of the magnetic flux Φ\Phi. We point out that the density of states and thus the ``strengh'' of the proximity effect can be tuned by the value of the flux inside the loop. Our results are fully consistent with recent experimental findings.Comment: 16 pages RevTeX, 23 Postscript figures, submitted to Phys. Rev.

    The development of interactive algorithms for the Mathematical Environment

    Get PDF
    AbstractThe Mathematical Environment which is under development at the Glushkov Institute of Cybernetics is a system of tools supporting the interactive manipulation of knowledge represented in the form of (formalized) mathematical texts. The system is implemented using a simulator for the Action Language, which has itself been developed using the algebraic programming system APS. The theoretical background of this project is the theory of interaction of agents and environments, constraint solving and the Evidence Algorithm. The main concepts underlying the project and the methodology of its development are explained in this paper in terms of the theory of interaction. The Evidence Algorithm is considered as an example of an interactive algorithm for the Mathematical Environment

    Wess-Zumino actions and Dirichlet Boundary Conditions for Super p-branes with Exotic Fractions of Supersymmetry

    Get PDF
    The general solutions in the models of closed and open superstring and super p-branes with exotic fractions of the N=1 supersymmetry are considered and the spontaneously broken character of the OSp(1,2M)OSp(1,2M) symmetry of the models is established. It is shown that extending these models by Wess-Zumino terms generates the Dirichlet boundary conditions for superstring and super p-branes. Using the generalized Wess-Zumino terms new OSp(1,2M)OSp(1,2M) invariant super p-brane and Dp-brane-like actions preserving M1M\frac{M-1}{M} fraction of supersymmetry are proposed. For M=32 these models suggest new superbrane vacua of M-theory preserving 31 from 32 global supersymmetries.Comment: Latex, 13 page

    The Rho-Meson as a Collective Excitation

    Full text link
    A model of the rho-meson as a collective excitation of qqˉq\bar{q} pairs in a system that obeys the modified Nambu--Jona-Lasinio Lagrangian is proposed. The rho emerges as a dormant Goldstone boson. The origin of the rho-meson mass is understood as a result of spontaneous chiral symmetry breaking. The low-energy dynamics of rho, pi, omega and gamma is consistently described in this new framework. The model accounts for the origin of the celebrated Kawarabayashi--Suzuki--Riazuddin--Fayyazuddin relation.Comment: 8 pages, plain LaTe

    The Momentum--Space Bosonization of the Nambu--Jona-Lasinio Model with Vector and Axial-Vector Mesons

    Full text link
    The momentum-space bosonization method is extended to the case of a Nambu--Jona-Lasinio type model with vector and axial-vector mesons. The method presented gives the possibility of deriving any meson vertex function to all orders in momenta and to the leading order in 1/Nc1/N_c. Two-point functions, which describe one-particle transitions to the hadronic vacuum, and meson self-energies are considered. We find new relations which generalize the well-known KSFR relation and both the first and the second Weinberg sum rules. These result from a consistent treatment of higher order terms in the momentum expansion.Comment: 11pp, TeX, CRN 93-5

    Charged particles accumulation in drift space of warm electron beam during non-stationary virtual cathod existence

    No full text
    In this paper, the properties and the formation of collective electromagnetic trap for electron beam that propagates in a conducting cylinder are described. It is shown that the electron beam provides the development of an electrostatic instability in the above-mentioned conditions. The instability leads to the appearance of a non-stationary virtual cathode and the formation of electrostatic potential trap. This phenomenon takes place in the central region of the drive space where the amplitude of the electrostatic potential has two maxima. The trap confines electrons during its formation and keeps them inside the drift tube. Once seized in the trap, electrons have rather low temperature and are unstable to diocotron oscillations. During the evolution of diocotron instability the spatial charge redistribution takes place in the cross-section of the beam, which is probably connected with the drift of electrons in longitudinal magnetic field. This process is accompanied not only by azimuthal redistribution of the beam density, but also by radial transfer of electrons across magnetic field, which leads to the increase of the radial beam dimensions and to the injection of electrons onto the walls of the drift chamber. The variations of the radial beam dimensions, and, hence, the spatial charge redistribution in longitudinal direction lead to the corresponding variation of the longitudinal distribution of electric potential, and appearance of self-consistent field of 'potential pit' type in central region of the drive space
    corecore