Physical Sciences and Mathematics Commons^™

Eigenvalues And Retardation Effects In The N=10 States Of Helium, Gordon W. F. Drake

Physics Publications

High-precision variational eigenvalues are obtained for the 10D, 10F, 10G and 10H states of helium by the application of multiple basis set methods. The accuracy is sufficient to provide the first definitive test of asymptotic expansion methods extensively developed by Drachmann (1982-8) for Rydberg states of high angular momentum. The results are also compared with recent high-precision measurements for the 10G-10H and 10F-10G transition frequencies, and interpreted in terms of predicted long-range retardation corrections. Bethe logarithms are calculated and Lamb shift corrections included. Small residual discrepancies persist which could be explained by uncalculated radiative shifts.

Predicted Energy Shifts For Paronic Helium, Gordon W. F. Drake

Physics Publications

It has been shown recently that one can construct a local relativistic quantum field theory which admits small violations of the Pauli exclusion principle by introducing paronic states which obey para-Fermi statistics of order 2. Paronic shifts are calculated for the low-lying states of helium to aid in the design of experiments either to detect paronic helium, or place upper limits on its possible existence. © 1989 The American Physical Society.

Optical And Electrochemical Studies Of Passive Film Formation In Amorphous Ni‐Cr‐P‐C Alloys, D. B. Hagan, B. W. Sloope, V. A. Niculescu

Physics Publications

The investigation of passivation of an amorphous Ni‐l4Cr‐17P‐0.5C alloy in lN H₂ SO₄ through anodic polarization and near‐normal optical reflectance is reported. It was found that the alloy passivates with a current density of 10^{− 1} A/m² extending to 1.0 V with current density dependent upon surface morphology. In the transpassive region under constant current density conditions the reflectance of the film exhibits strong interference phenomena and overall exponential decay in intensity. The behavior of the system in this region is described with a single thin‐film optical model consistent with the formation of a chromium …

Calculations Of Scattered Light From Rigid Polymers By Shifrin And Rayleigh-Debye Approximations, M. F. Bishop

Physics Publications

ABSTRACT

We show that the commonly used Rayleigh-Debye method for calculating light scattering can lead to significant errors when used for describing scattering from dilute solutions of long rigid polymers, errors that can be overcome by use of the easily applied Shifrin approximation. In order to show the extent of the discrepancies between the two methods, we have performed calculations at normal incidence both for polarized and unpolarized incident light with the scattering intensity determined as a function of polarization angle and of scattering angle, assuming that the incident light is in a spectral region where the absorption of hemoglobin …