Determination of Newton's gravitational constant, G, with improved precision Status report, 1 Apr. - 30 Sep. 1965

Apparatus and techniques for laboratory determination of Newtonian gravitation constan

The Structure of Renal Corpuscle in the Sparrow, Passer domesticus domesticus, as Revealed by the Electron Microscope

Light microscope studies on the structure of the renal corpuscle have been made by numerous investigators. Among these were Bowman (1842), Vimtrup (1928), von Mollendorff (1928), Bargmann (1929), Zimmermann (1929), McGregor (1929), Bensley and Bensley (1930), and many others. A diversity of opinions arose concerning the details of structure of the mammalian renal corpuscle which was to remain, to a certain extent, the legacy of the electron · microscopists. Among the electron microscopists who studied the structure of the mammalian renal corpuscle were Pease and Baker (1950), Dalton (1951), Oberling, Gautier and Bernhard (1951), Hall, Roth and Johnson (1953), Jones ( 1953), Rinehart, Farguhar, Jung and Abul-Haj (1953), Reid (1954), Hall and Roth (1954), Mueller, Mason and Stout (1955), and Pease (1955). Some of the points of disagreement on the structural features of the renal corpuscle are: (1) basement membrane of Bowman\u27s capsule, (2) epithelium of Bowman\u27s capsule, (3) epithelium of the glomerulus, (4) basement membrane of the glomerulus, and (5) endothelium of the glomerulus. Since studies with the electron microscope on the vertebrate renal corpuscle have been limited to mammals it seemed of interest to attempt an analysis of the bird\u27s renal corpuscle by this method

Determination of newton's gravitational con- stant, g, with improved precision status report, oct. 1, 1964 - mar. 31, 1965

Determination of Newton gravitational constant with improved precisio

Clone flow analysis for a theory inspired Neutrino Experiment planning

The presence of several clone solutions in the simultaneous measurement of ($\theta_{13},\delta$) has been widely discussed in literature. In this letter we write the analytical formulae of the clones location in the ($\theta_{13},\delta$) plane as a function of the physical input pair ($\bar\theta_{13},\bar\delta$). We show how the clones move with changing $\bar\theta_{13}$. The "clone flow" can be significantly different if computed (naively) from the oscillation probabilities or (exactly) from the probabilities integrated over the neutrino flux and cross-section. Using our complete computation we compare the clone flow of a set of possible future neutrino experiments: the CERN SuperBeam, BetaBeam and Neutrino Factory proposals. We show that the combination of these specific BetaBeam and SuperBeam does not help in solving the degeneracies. On the contrary, the combination of one of them with the Neutrino Factory Golden and Silver channel can be used, from a theoretical point of view, to solve completely the eightfold degeneracy.Comment: 23 pages, using epsfi

Observation of the nonlinear Hall effect under time reversal symmetric conditions

The electrical Hall effect is the production of a transverse voltage under an out-of-plane magnetic field. Historically, studies of the Hall effect have led to major breakthroughs including the discoveries of Berry curvature and the topological Chern invariants. In magnets, the internal magnetization allows Hall conductivity in the absence of external magnetic field. This anomalous Hall effect (AHE) has become an important tool to study quantum magnets. In nonmagnetic materials without external magnetic fields, the electrical Hall effect is rarely explored because of the constraint by time-reversal symmetry. However, strictly speaking, only the Hall effect in the linear response regime, i.e., the Hall voltage linearly proportional to the external electric field, identically vanishes due to time-reversal symmetry. The Hall effect in the nonlinear response regime, on the other hand, may not be subject to such symmetry constraints. Here, we report the observation of the nonlinear Hall effect (NLHE) in the electrical transport of the nonmagnetic 2D quantum material, bilayer WTe2. Specifically, flowing an electrical current in bilayer WTe2 leads to a nonlinear Hall voltage in the absence of magnetic field. The NLHE exhibits unusual properties sharply distinct from the AHE in metals: The NLHE shows a quadratic I-V characteristic; It strongly dominates the nonlinear longitudinal response, leading to a Hall angle of about 90 degree. We further show that the NLHE directly measures the "dipole moment" of the Berry curvature, which arises from layer-polarized Dirac fermions in bilayer WTe2. Our results demonstrate a new Hall effect and provide a powerful methodology to detect Berry curvature in a wide range of nonmagnetic quantum materials in an energy-resolved way

Neutral currents and tests of three-neutrino unitarity in long-baseline experiments

We examine a strategy for using neutral current measurements in long-baseline neutrino oscillation experiments to put limits on the existence of more than three light, active neutrinos. We determine the relative contributions of statistics, cross section uncertainties, event misidentification and other systematic errors to the overall uncertainty of these measurements. As specific case studies, we make simulations of beams and detectors that are like the K2K, T2K, and MINOS experiments. We find that the neutral current cross section uncertainty and contamination of the neutral current signal by charge current events allow a sensitivity for determining the presence of sterile neutinos at the 0.10--0.15 level in probablility.Comment: 24 pages, Latex2e, uses graphicx.sty, 2 postscript figures. Submitted to the Neutrino Focus Issue of New Journal Physics at http://www.njp.or

Density-functional theory of elastically deformed finite metallic system: work function and surface stress

The effect of external strain on surface properties of simple metals is considered within the modified stabilized jellium model. The equations for the stabilization energy of the deformed Wigner-Seitz cells are derived as a function of the bulk electron density and the given deformation. The results for surface stress and work function of aluminium calculated within the self-consistent Kohn-Sham method are also given. The problem of anisotropy of the work function of finite system is discussed. A clear explanation of independent experiments on stress-induced contact potential difference at metal surfaces is presented.Comment: 15 pages, 1 figur

Quantifying defects in graphene via Raman spectroscopy at different excitation energies.

We present a Raman study of Ar(+)-bombarded graphene samples with increasing ion doses. This allows us to have a controlled, increasing, amount of defects. We find that the ratio between the D and G peak intensities, for a given defect density, strongly depends on the laser excitation energy. We quantify this effect and present a simple equation for the determination of the point defect density in graphene via Raman spectroscopy for any visible excitation energy. We note that, for all excitations, the D to G intensity ratio reaches a maximum for an interdefect distance ∼3 nm. Thus, a given ratio could correspond to two different defect densities, above or below the maximum. The analysis of the G peak width and its dispersion with excitation energy solves this ambiguity