Reduction of the Three Dimensional Schrodinger Equation for Multilayered Films

In this paper, we present a method for reducing the three dimensional Schrodinger equation to study confined metallic states, such as quantum well states, in a multilayer film geometry. While discussing some approximations that are employed when dealing with the three dimensionality of the problem, we derive a one dimensional equation suitable for studying such states using an envelope function approach. Some applications to the Cu/Co multilayer system with regard to spin tunneling/rotations and angle resolved photoemission are discussed.Comment: 14 pages, 1 figur

Current-Driven Magnetization Dynamics in Magnetic Multilayers

We develop a quantum analog of the classical spin-torque model for current-driven magnetic dynamics. The current-driven magnetic excitation at finite field becomes significantly incoherent. This excitation is described by an effective magnetic temperature rather than a coherent precession as in the spin-torque model. However, both the spin-torque and effective temperature approximations give qualitatively similar switching diagrams in the current-field coordinates, showing the need for detailed experiments to establish the proper physical model for current-driven dynamics.Comment: 5 pages, 2 figure

Influence of a Uniform Current on Collective Magnetization Dynamics in a Ferromagnetic Metal

We discuss the influence of a uniform current, $\vec{j}$, on the magnetization dynamics of a ferromagnetic metal. We find that the magnon energy $\epsilon(\vec{q})$ has a current-induced contribution proportional to $\vec{q}\cdot \vec{\cal J}$, where $\vec{\cal J}$ is the spin-current, and predict that collective dynamics will be more strongly damped at finite ${\vec j}$. We obtain similar results for models with and without local moment participation in the magnetic order. For transition metal ferromagnets, we estimate that the uniform magnetic state will be destabilized for $j \gtrsim 10^{9} {\rm A} {\rm cm}^{-2}$. We discuss the relationship of this effect to the spin-torque effects that alter magnetization dynamics in inhomogeneous magnetic systems.Comment: 12 pages, 2 figure

Consistency of the mass variation formula for black holes accreting cosmological fluids

We address the spherical accretion of generic fluids onto black holes. We show that, if the black hole metric satisfies certain conditions, in the presence of a test fluid it is possible to derive a fully relativistic prescription for the black hole mass variation. Although the resulting equation may seem obvious due to a form of it appearing as a step in the derivation of the Schwarzschild metric, this geometrical argument is necessary to fix the added degree of freedom one gets for allowing the mass to vary with time. This result has applications on cosmological accretion models and provides a derivation from first principles to serve as a base to the accretion equations already in use in the literature.Comment: 4 pages, 1 figure. To appear in Gen. Rel. Gra

Multicentre evaluation of the Roche Elecsys® Active B12 (holotranscobalamin) electro-chemiluminescence immunoassay

Background: Vitamin B12 deficiency is a common disorder. In circulation, vitamin B12 is bound to transcobalamin (holotranscobalamin), which is considered the active form of cobalamin. The objective of this study was to evaluate the analytical performance of the Roche Elecsys Active B12 immunoassay. Methods: Limit of quantification and linearity were assessed according to CLSI EP17-A2 and EP-6A guidelines. Precision and bias of Roche Active B12 test against Architect ci8200 (Abbott) were performed according to CLSI EP-5 A3 guideline at three Euro

Dynamically generated resonances from the vector octet-baryon decuplet interaction

We study the interaction of the octet of vector mesons with the decuplet of baryons using Lagrangians of the hidden gauge theory for vector interactions. The unitary amplitudes in coupled channels develop poles that can be associated with some known baryonic resonances, while there are predictions for new ones at the energy frontier of the experimental research. The work offers guidelines on how to search for these resonances

Search for the Rare Decays J/Psi --> Ds- e+ nu_e, J/Psi --> D- e+ nu_e, and J/Psi --> D0bar e+ e-

We report on a search for the decays J/Psi --> Ds- e+ nu_e + c.c., J/Psi --> D- e+ nu_e + c.c., and J/Psi --> D0bar e+ e- + c.c. in a sample of 5.8 * 10^7 J/Psi events collected with the BESII detector at the BEPC. No excess of signal above background is observed, and 90% confidence level upper limits on the branching fractions are set: B(J/Psi --> Ds- e+ nu_e + c.c.)<4.8*10^-5, B(J/Psi --> D- e+ nu_e + c.c.) D0bar e+ e- + c.c.)<1.1*10^-5Comment: 10 pages, 4 figure

Measurements of J/psi Decays into 2(pi+pi-)eta and 3(pi+pi-)eta

Based on a sample of 5.8X 10^7 J/psi events taken with the BESII detector, the branching fractions of J/psi--> 2(pi+pi-)eta and J/psi-->3(pi+pi-)eta are measured for the first time to be (2.26+-0.08+-0.27)X10^{-3} and (7.24+-0.96+-1.11)X10^{-4}, respectively.Comment: 11 pages, 6 figure

Measurements of Cabibbo Suppressed Hadronic Decay Fractions of Charmed D0 and D+ Mesons

Using data collected with the BESII detector at $e^{+}e^{-}$ storage ring Beijing Electron Positron Collider, the measurements of relative branching fractions for seven Cabibbo suppressed hadronic weak decays $D^0 \to K^- K^+$, $\pi^+ \pi^-$, $K^- K^+ \pi^+ \pi^-$ and $\pi^+ \pi^+ \pi^- \pi^-$, $D^+ \to \bar{K^0} K^+$, $K^- K^+ \pi^+$ and $\pi^- \pi^+ \pi^+$ are presented.Comment: 11 pages, 5 figure

BESII Detector Simulation

A Monte Carlo program based on Geant3 has been developed for BESII detector simulation. The organization of the program is outlined, and the digitization procedure for simulating the response of various sub-detectors is described. Comparisons with data show that the performance of the program is generally satisfactory.Comment: 17 pages, 14 figures, uses elsart.cls, to be submitted to NIM