5,614 research outputs found

    Theory of Fermionic superfluid with SU(2)xSU(6) symmetry

    Full text link
    We study theoretically interspecies Cooper pairing in a fermionic system with SU(2)xSU(6) sym- metry. We show that, with suitable unitary transformations, the order parameter for the ground state can be reduced to only two non-vanishing complex components. The ground state has a large degeneracy. We find that while some Goldstone modes have linear dispersions, others are quadratic at low frequencies. We compare our results with the case of SU(N).Comment: extended version; include comparison with SU(N

    Basic Properties of a Vortex in a Noncentrosymmetric Superconductor

    Full text link
    We numerically study the vortex core structure in a noncentrosymmetric superconductor such as CePt3Si without mirror symmetry about the xy plane. A single vortex along the z axis and a mixed singlet-triplet Cooper pairing model are considered. The spatial profiles of the pair potential, local density of states, supercurrent density, and radially-textured magnetic moment density around the vortex are obtained in the clean limit on the basis of the quasiclassical theory of superconductivity.Comment: 6 pages; submitted to Proc. of VORTEX I

    Tracking system analytic calibration activities for the Mariner Mars 1971 mission

    Get PDF
    Data covering various planning aspects of Mariner Mars 1971 mission are summarized. Data cover calibrating procedures for tracking stations, radio signal propagation in the troposphere, effects of charged particles on radio transmission, orbit calculation, and data smoothing

    Center of mass and relative motion in time dependent density functional theory

    Full text link
    It is shown that the exchange-correlation part of the action functional Axc[ρ(r,t)]A_{xc}[\rho (\vec r,t)] in time-dependent density functional theory , where ρ(r,t)\rho (\vec r,t) is the time-dependent density, is invariant under the transformation to an accelerated frame of reference ρ(r,t)ρ(r,t)=ρ(r+x(t),t)\rho (\vec r,t) \to \rho ' (\vec r,t) = \rho (\vec r + \vec x (t),t), where x(t)\vec x (t) is an arbitrary function of time. This invariance implies that the exchange-correlation potential in the Kohn-Sham equation transforms in the following manner: Vxc[ρ;r,t]=Vxc[ρ;r+x(t),t]V_{xc}[\rho '; \vec r, t] = V_{xc}[\rho; \vec r + \vec x (t),t]. Some of the approximate formulas that have been proposed for VxcV_{xc} satisfy this exact transformation property, others do not. Those which transform in the correct manner automatically satisfy the ``harmonic potential theorem", i.e. the separation of the center of mass motion for a system of interacting particles in the presence of a harmonic external potential. A general method to generate functionals which possess the correct symmetry is proposed

    The Nedd4-2/Ndfip1 axis is a negative regulator of IgE-mediated mast cell activation

    Get PDF
    Cross-linkage of the high-affinity immunoglobulin E (IgE) receptor (FceRI) on mast cells by antigen ligation has a critical role in the pathology of IgE-dependent allergic disorders, such as anaphylaxis and asthma. Restraint of intracellular signal transduction pathways that promote release of mast cell-derived pro-inflammatory mediators is necessary to dampen activation and restore homoeostasis. Here we show that the ligase Nedd4-2 and the adaptor Ndfip1 (Nedd4 family interacting protein 1) limit the intensity and duration of IgE-FceRI-induced positive signal transduction by ubiquitinating phosphorylated Syk, a tyrosine kinase that is indispensable for downstream FceRI signalosome activity. Importantly, loss of Nedd4-2 or Ndfip1 in mast cells results in exacerbated and prolonged IgE-mediated cutaneous anaphylaxis in vivo. Our findings reveal an important negative regulatory function for Nedd4-2 and Ndfip1 in IgE-dependent mast cell activity.Kwok Ho Yip, Natasha Kolesnikoff, Nicholas Hauschild, Lisa Biggs, Angel F. Lopez, Stephen J. Galli, Sharad Kumar, Michele A. Grimbaldesto
    corecore