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    Theory of Polar Corrections to Donor Binding

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    We calculate the optical phonon correction to the binding energy of electrons to donors in cubic materials. Previous theories calculated the Rydberg energy reduced by the effective mass and the static dielectric function. They omitted an important energy term from the long-range polarization of the ionized donor, which vanishes for the neutral donor. They also omitted the donor-phonon interaction. Including these terms yields a new formula for the donor binding energy

    Sensitivity of Cross Sections for Elastic Nucleus-Nucleus Scattering to Halo Nucleus Density Distributions

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    In order to clear up the sensitivity of the nucleus-nucleus scattering to the nuclear matter distributions of exotic halo nuclei, we have calculated differential cross sections for elastic scattering of the 6^6He and 11^{11}Li nuclei on several nuclear targets at the energy of 0.8 GeV/nucleon with different assumed nuclear density distributions in 6^6He and 11^{11}Li.Comment: 10 pages, 7 figures. Submitted to Proceedings of the 61 International Conference "Nucleus-2011" on the Problems of the Nuclear Spectroscopy and the Atomic Nuclear Structure, Sarov Nijzegorodskaya district, October 10-14, 201

    Note on nonequilibrium stationary states and entropy

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    In transformations between nonequilibrium stationary states, entropy might be a not well defined concept. It might be analogous to the ``heat content'' in transformations in equilibrium which is not well defined either, if they are not isochoric ({\it i.e.} do involve mechanical work). Hence we conjecture that un a nonequilbrium stationary state the entropy is just a quantity that can be transferred or created, like heat in equilibrium, but has no physical meaning as ``entropy content'' as a property of the system.Comment: 4 page

    Shear viscosity in magnetized neutron star crust

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    The electron shear viscosity due to Coulomb scattering of degenerate electrons by atomic nuclei throughout a magnetized neutron star crust is calculated. The theory is based on the shear viscosity coefficient calculated neglecting magnetic fields but taking into account gaseous, liquid and solid states of atomic nuclei, multiphonon scattering processes, and finite sizes of the nuclei albeit neglecting the effects of electron band structure. The effects of strong magnetic fields are included in the relaxation time approximation with the effective electron relaxation time taken from the field-free theory. The viscosity in a magnetized matter is described by five shear viscosity coefficients. They are calculated and their dependence on the magnetic field and other parameters of dense matter is analyzed. Possible applications and open problems are outlined.Comment: 6 pages, 3 figures, EPL, accepte

    The antifield Koszul-Tate complex of reducible Noether identities

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    A generic degenerate Lagrangian system of even and odd fields is examined in algebraic terms of the Grassmann-graded variational bicomplex. Its Euler-Lagrange operator obeys Noether identities which need not be independent, but satisfy first-stage Noether identities, and so on. We show that, if a certain necessary and sufficient condition holds, one can associate to a degenerate Lagrangian system the exact Koszul-Tate complex with the boundary operator whose nilpotency condition restarts all its Noether and higher-stage Noether identities. This complex provides a sufficient analysis of the degeneracy of a Lagrangian system for the purpose of its BV quantization.Comment: 23 page

    Active vibration isolator for flexible bodies Patent

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    Vibration control of flexible bodies in steady accelerating environmen

    Network representation of electromagnetic fields and forces using generalized bond graphs

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    We show that it is possible to describe electromagnetic (E-M) fields with a generalized network representation (generalized bond graphs). E-M fields inmoving matter, forces due to E-M fields (Lorentz force, ets.) and field transformations are included in the network description. The relations of these E-M phenomena with respect to each other are clearly represented by the bond graph. We also show that it is not possible to describe E-M phenomena in moving matter with conventional bond graphs, but that a generalized bond graph concept is required.\ud \ud The description of simple E-M devices with conventional bond graphs is based on rather drastic assumptions, i.e. quasi-static conditions (E-M radiation neglected), homogeneous fields, isotropic linear material, etc. These assumptions are not made in this paper
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