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.
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.
The optical waveguide lens is an important and basic component in many integrated optical devices, performing such functions as focussing and collimating, Fourier transformation and optical signal processing. For many...
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The optical waveguide lens is an important and basic component in many integrated optical devices, performing such functions as focussing and collimating, Fourier transformation and optical signal processing. For many applications of the optical waveguide lens, diffraction-limited performance is required. Such a stringent focussing criterion necessitates careful control of the design parameters and fabrication procedure, as well as the in situ variables which may affect the lens performance. The design and performance of geodesic lenses and grating lenses have been treated in the past. However, for the mode-index lens, among which the Luneburg lens' shown in Fig. 1, is perhaps the most common, no complete examination of the fabrication tolerances has been made.
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.
作者：
J. J. SimpsonDepartment of Physics
Guelph-Waterloo Program for Graduate Work in Physics University of Guelph Guelph Ontario Canada N1G 2W1
The half-life of tritium implanted into a Si(Li) x-ray detector has been determined to be 12.32±0.03 yr by following the decay for about 5.5 years. Using a recently determined β-decay end-point energy for the sa...
The half-life of tritium implanted into a Si(Li) x-ray detector has been determined to be 12.32±0.03 yr by following the decay for about 5.5 years. Using a recently determined β-decay end-point energy for the same system, the product (GA/GV)〈στ〉 for tritium has been determined to be 2.094±0.004.
Laser measurements at 23.13 cm? 1 of collision‐induced absorption are described using absorption cells over 1500 cm in length and a liquid‐helium‐cooled bolometer. Also reported are a number of improvements over a ...
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Laser measurements at 23.13 cm?1 of collision‐induced absorption are described using absorption cells over 1500 cm in length and a liquid‐helium‐cooled bolometer. Also reported are a number of improvements over a previously described system operating at different laser frequencies. The improvements are related to the method of data collection and operation of the system which result in an increased accuracy of determination of the absorption coefficients of nonpolar condensed gases. Typical results are given for the cells used in the temperature range from 126 to 410 K at pressures up to 1500 psi.
Emission in the visible has been observed from dense, cold helium gas in contact with solid hydrogen when irradiated by a 15-MeV proton beam. All four stable isotopic combinations have been studied, and the spectrum o...
Emission in the visible has been observed from dense, cold helium gas in contact with solid hydrogen when irradiated by a 15-MeV proton beam. All four stable isotopic combinations have been studied, and the spectrum of one of them, HeD4, appears highly perturbed. Spectral identification of rotational features and a plausible explanation of the perturbation have been provided by rovibrational energy-level calculations.
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