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Displaying 2576 - 2600 of 2609

Transfer function approach to the experimental determination of mode transfer matrices

July 20, 1990
Author(s)
Shao Yang, Igor Vayshenker, D. R. Hjelme, I. P. Januar, A. R. Mickelson
An improved scheme for characterization of multimode fiber systems is investigated. Characterization with transfer matrices requires multiple measurements for each component. The transfer function approach herein investigated requires only a single launch

Editorial

February 1, 1990
Author(s)
R. S. Turgel

Transfer function analysis of measured transfer matrices

August 1, 1989
Author(s)
Shao Yang, Igor Vayshenker, A. R. Mickelson
Measurements of mode transfer matrices of various multimode fiber optic connectors are presented. To analyze the accuracy and repeatability of such measurements, a theoretical framework which employs mode transmission functions is derived. It is shown that

Improved Low-Energy Diffuse Scattering Electron-Spin Polarization Analyzer

January 1, 1989
Author(s)
M Scheinfein, Daniel T. Pierce, John Unguris, Jabez J. McClelland, Robert Celotta, Michael H. Kelley
An improved low-energy diffuse scattering electron-spin polarization analyzer is described. It is based on the low-energy (150 eV) diffuse scattering of polarized electrons from polycrystalline evaporated Au targets. By collecting large solid angles and

Electron Spin Polarization Analyzers for Use with Synchrotron Radiation

April 1, 1988
Author(s)
Daniel T. Pierce, Robert Celotta, Michael H. Kelley, John Unguris
The measurement of the spin polarization of photoelectrons emitted from a magnetic material is discussed. An important consideration is the acceptance phase space of the spin analyzer relative to the phase space of the photoemitted electrons to be measured

Frequency Dependencies of Precision Resistors

February 1, 1988
Author(s)
R D. Cutkosky
A variety of ac and dc resistors were examined for frequency dependence from dc to 400 Hz. It is concluded that several choices are available for use as standards in resistance thermometry.

Viscometer for low frequency, low shear rate measurements

August 1, 1986
Author(s)
Robert F. Berg, Michael R. Moldover
We describe a torsion-oscillator viscometer whose low frequency ( 0.5 Hz) and very low shear rate (0.05 s-1) are required for measurements of shear sensitive fluids such as microemulsions, polymer melts and solutions gels, and liquid mixtures near critical

Low Energy Diffuse Scattering Electron Spin Polarization Analyzer

January 1, 1986
Author(s)
John Unguris, Daniel T. Pierce, Robert Celotta
A new, compact (approximately fist sized), efficient electron-spin analyzer is described. It is based on low-energy (150 eV) diffuse scattering from a high-Z target, for example, an evaporated polycrystalline Au film opaque to the incident electron beam

An Intense Source of Monochromatic Electrons: Photoemission from GaAs

January 1, 1984
Author(s)
C Feigerle, Daniel T. Pierce, A Seiler, Robert Celotta
Measurements of intensity and width of the energy distribution for photoemission from negative electron affinity GaAs have been made as a function of surface preparation and temperature. Energy distributions as narrow as 31 meV (full width at half-maximum)

A UHV-Gasket Removal Tool

March 1, 1983
Author(s)
B Waclawski
This note describes a safe, effective tool for removing copper gaskets from ultrahigh vacuum flanges. Use of the tool practically reduces to zero the chance of damaging the flange sealing surface, because all motion of the tool is away from the flange face
Displaying 2576 - 2600 of 2609