It is shown that the generalised non-local model pseudopotential theory, developed recently, can be applied to the calculation of the thermodynamic properties of liquid metallic Li and Be in a fashion similar to its a...
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It is shown that the generalised non-local model pseudopotential theory, developed recently, can be applied to the calculation of the thermodynamic properties of liquid metallic Li and Be in a fashion similar to its application to the transition metals. The corrections to the effective ionic interaction attributed to one-body plus two-body terms are much less important than those from the three-body plus higher-body terms. In analogy to sd-mixing in the transition metals, the latter are interpreted as arising from sp-mixing effects. These corrections have relatively similar magnitudes in the calculation of the phonon spectra of Li and Be and the latter corrections are required to yield reasonable agreement with observation. Finally, the Be results vindicate the physical interpretation.
Spectra have been recorded from monochromatized Kα 1 , Kβ 1 and Lα 1 X-rays in the 3—16 keV energy region incident on an Si(Li) detector. An analytic lineshape consisting of a Gaussian plus two Gaussian-exponentia...
Spectra have been recorded from monochromatized Kα 1 , Kβ 1 and Lα 1 X-rays in the 3—16 keV energy region incident on an Si(Li) detector. An analytic lineshape consisting of a Gaussian plus two Gaussian-exponential convolutes fits these well, except at very low energy. The intensities and parameters of these tails are explored in the context of the processes responsible, and the behaviour of the shorter tail is compared with the predictions of a model calculation of Auger and photoelectron escape. The well behaved energy dependence of the tailing parameters improves the prospects for more accurate fitting of complex XRF, EPMA and PIXE spectra.
The various mechanisms giving rise to low-energy peak tailing in Si(Li) X-ray detectors are discussed. The Hypermet lineshape function is shown to be satisfactory in the energy range 4–15 keV. Stringent tests of the ...
The various mechanisms giving rise to low-energy peak tailing in Si(Li) X-ray detectors are discussed. The Hypermet lineshape function is shown to be satisfactory in the energy range 4–15 keV. Stringent tests of the X-ray relative intensity database used in PIXE, performed with detectors of accurately known lineshape, lend it strong support. Current measurements of the L subshell fluorescence and Coster-Kronig yields indicate that the latter may be systematically lower than theory.
We describe the results of the numerical integration of the equations of motion of a 17-particle chain with fixed ends and linear and cubic nearest-neighbour forces. Detailed graphs of mode energies, mode trajectories...
We describe the results of the numerical integration of the equations of motion of a 17-particle chain with fixed ends and linear and cubic nearest-neighbour forces. Detailed graphs of mode energies, mode trajectories, variation of the orbit periods and the squared modulus of the discrete Fourier transforms of mode displacements are shown for the case of the chain excited from rest in the 11th mode. The total system energy is always conserved to better than 0.02%. An additional 100 histories of this chain were calculated and stored for the same starting energy and a variety of starting velocities and displacements of the 11th mode. The data gathered constituted a constant energy ensemble. A coarse grained energy distribution function and corresponding Boltzmann H -functions were calculated for each mode. These H -functions proved to drop reversibly with time to a minimum value, indicating that each mode has reached a statistical equilibrium state. The mode energy distribution functions in this equilibrium state are shown to take a Maxwell-Boltzmann form. The associated mode temperatures range in value over two orders of magnitude.
The lattice vibrations and internal modes of polycrystalline CH 2 I 2 and CD 2 I 2 have been studied as a function of temperature using Raman and far-infrared spectroscopy. CH 2 I 2 has two stable phases, one of which...
The lattice vibrations and internal modes of polycrystalline CH 2 I 2 and CD 2 I 2 have been studied as a function of temperature using Raman and far-infrared spectroscopy. CH 2 I 2 has two stable phases, one of which is metastable in the temperature range of the other, and a second metastable phase. CD 2 I 2 has only one solid phase. Possible structures for the various phases are discussed.
The rotational structure of the D 2 Σ + →A 2 Σ + transition of 4 HeD is highly perturbed, and this is caused by the near degeneracy of the D, ν=0 and C, ν=3 vibrational levels. A perturbation analysis is presente...
The rotational structure of the D 2 Σ + →A 2 Σ + transition of 4 HeD is highly perturbed, and this is caused by the near degeneracy of the D, ν=0 and C, ν=3 vibrational levels. A perturbation analysis is presented which yields the spectroscopic constants for both of the perturbing levels, yielding the first experimental information on a vibrationally excited state of HeH.
作者：
ALEXANDER, MEDepartment of Physics
Guelph-Waterloo Program for Graduate Work in Physics University of Guelph Guelph Ontario N1G 2W1 Canada
The gravitational potential energy of tidal interactions in a binary system is formulated as a perturbation Hamiltonian which couples the normal mode oscillations of the stars with their orbital motion in a self-consi...
The gravitational potential energy of tidal interactions in a binary system is formulated as a perturbation Hamiltonian which couples the normal mode oscillations of the stars with their orbital motion in a self-consistent way. The stellar oscillations are treated in the linear approximation for a non-rotating star. In order to examine resonances between normal mode oscillations and orbital motion, the Hamiltonian is transformed to action-angle variables of the zero-order problem. Approximate expressions are derived for the case of small orbital eccentricities and a pair of dominant stellar eigenmodes, characterized by a single value of the azimuthal indexm. The positions of exact resonance and motion in the vicinity of resonance is *** integration is performed on the tidal capture of two stars, using the self-consistent treatment. Angular momentum transferred to the stars as a result of tidal interactions is sufficiently large to invalidate the assumption (Press & Teukolsky) that the stars’ rotation can be ignored.
Tom Riddolls, Kartik Shanker; Multiple‐sample holder for in situ thin‐film deposition and analysisMultiple‐sample holder for in situ thin‐film deposition, Journ
Tom Riddolls, Kartik Shanker; Multiple‐sample holder for in situ thin‐film deposition and analysisMultiple‐sample holder for in situ thin‐film deposition, Journ
A frequency response technique for measuring carrier and trap lifetimes in semiconductors has been developed for use with a scanning laser microscope. Electron-hole pairs are excited in the semiconductor specimen usin...
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In a previous paper, we presented general eigenvalue equations for both transverse-electric (TE) and transverse-magnetic (TM) modes in multilayer slab waveguides. Here, those formulas are applied to symmetric periodic...
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In a previous paper, we presented general eigenvalue equations for both transverse-electric (TE) and transverse-magnetic (TM) modes in multilayer slab waveguides. Here, those formulas are applied to symmetric periodic stratified media. The results obtained are compared with those of Yeh et al, which were obtained by using matrix method. The eigenvalue equations for even and odd-modes are also obtained.
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