A study of earth radar returns from Alouette satellite
Ground radar reflection coefficient analysis on Alouette sounder ionograms
Chia, R. C.↗
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Infrared optical properties of water and ice spheres.
IR absorption coefficient, reflectivity and complex index of refraction of ice and water spheres, calculating single scattering albedo, asymmetry factor and extinction cross section
Irvine, W. M.↗
Ionospheric sounder as a means of monitoring ground moisture
Ionospheric sounding for monitoring effective reflection coefficient of ground moisture
Fung, A. K.↗
Some factors affecting electromagnetic detection of lunar subsurface water.
Lunar surface pore water /or ice/ detection by active orbital or surface electromagnetic experiments, noting water effect on reflection coefficient
Jiracek, G. R.↗
On the scattering parameters of a reduced multiport
Reduced multiport equivalent scattering parameters derivation by matrix method, determining load reflection coefficients effect on signal attenuation and phase shift
Otoshi, T. Y.↗
Radiation of sound from an unflanged circular duct with flow
Sound radiation from unflanged circular waveguide duct with flow, calculating reflection coefficients, directivity pattern and power for comparison with approximate methods
Drischler, J. A.↗
X-ray spectrometric properties of potassium acid phthalate crystals
Potassium acid phthalate crystal X ray spectrometric properties measurements, discussing parallel position rocking curves and reflection coefficients
Hanzely, S.↗
Electron and bremsstrahlung penetration and dose calculation
Calculation of electron and bremsstrahlung dose deposition with energy deposition, transmission, and reflection coefficients for electrons
Burrell, M. O.↗
Electron and bremsstrahlung penetration and dose calculation
Various techniques for the calculation of electron and bremsstrahlung dose deposition are described. Energy deposition, transmission, and reflection coefficients for electrons incident on plane slabs are presented, and methods for their use in electron dose calculations were developed. A method using the straight-ahead approximation was also developed, and the various methods were compared and found to be in good agreement. Both accurate and approximate methods of calculating bremsstrahlung dose were derived and compared. Approximation is found to give a good estimate of dose where the electron spectrum falls off exponentially with energy.
Watts, J. W., Jr.↗
Work function measurements by the field emission retarding potential method
Using the field emission retarding potential method true work functions have been measured for the following monocrystalline substrates: W(110), W(111), W(100), Nb(100), Ni(100), Cu(100), Ir(110) and Ir(111). The electron elastic and inelastic reflection coefficients from several of these surfaces have also been examined near zero primary beam energy.
Swanson, L. W.↗
Interpretation of dispersion relations for bounded systems.
Treatment of the problem of constructing normal modes for an arbitrarily bounded system from roots of the linear dispersion relation D(omega, k) = 0 for the corresponding infinite or periodically bounded system. For a system described by continuous macroscopic variables, and of general cylindrical form, each transverse eigenmode gives rise to a set of axial normal modes constructed from a pair of dominant roots of D = 0 satisfying the boundary conditions which are characterized by complex reflection coefficients for the dominant waves. The implications of the results for the interpretation of experiments on plasma waves and instabilities on finite cylinders are discussed, with particular reference to the effects of end-plate damping and axial current on Q-machines.
Rognlien, T. D.↗
Bistatic radar measurements of the surface of Mars with Mariner 1969.
The detection of echoes produced by oblique reflection of the RF (2300 MHz) spacecraft carrier from the Martian surface as Mariner 6 and 7 flew behind Mars in 1969, is described. Changes in echo center frequency and bandwidth are utilized to study the radius and roughness of the surface along a quasi-specular radar track that led from an optically dark and densely cratered region of Meridiani Sinus over into a smoother and brighter looking area of Thymiamata. A 3 to 1 decrease in surface roughness of large size compared to the wavelength (13 cm) was observed as the reflecting zone moved across the boundary between these two regions. The average radius obtained along the track was 3393 plus or minus 3 km. Due to large angles of incidence (86 to 90 deg), and surface shadowing, the data are not suitable for mapping the reflection coefficient of the surface material.
Fjeldbo, G.↗
Some methods for determining the profile functions of inhomogeneous media
The problem of determining the electric permittivity of an inhomogeneous dielectric medium is considered. Two analytical methods and one numerical method for solving this problem are presented. All these methods utilize the reflection coefficient measured as a function of the angular spectrum variable. This allows measurements at a fixed frequency, and these methods, therefore, can be used when the medium being studied is dispensive. A few examples are provided and some comments are made regarding the stability of solutions obtained using the various methods.
Mittra, R.↗
Low-frequency macroscopic instabilities of fully ionized magnetoplasma
Studies are described of low-frequency quasi-static instabilities in a fully ionized plasma. The plasma is assumed to be immersed in a uniform magnetic field, and is either uniform or has a number density gradient perpendicular to the magnetic field. A moment equation description of the ion and electron dynamics is used; collisions are assumed to have a strong effect on electron motion along the magnetic field. Before considering specific modes, a stability analysis is developed which allows a classification of wave growth characteristics to be made for a bounded system from solutions to the dispersion relation for an infinite system. Also, a method is given for calculating the normal mode frequencies and wave profiles by using the reflection coefficients at the boundaries. For wave propagation perpendicular to the magnetic field, the flute wave is studied in cylindrical geometry. The destabilizing effect of a radial electric field is considered by solving a differential equation.
Rognlien, T. D.↗
High performance S-band horn antennas for radiometer use
Horn antennas of four types: pyramidal corrugated, conical corrugated, pyramidal dual mode and conical dual mode, have been constructed and evaluated for use as S-band radiometer antennas. Each of the structures is described and radiation patterns and impedance and resistive loss measurements including a layer of foreign material on a thin radome, are presented. A precision method for determining reflection losses is described using a multiprobe reflectometer technique. The same technique is also applied to the measurement of resistive losses by closing the ends of the antennas with short circuit plates and determining the losses from an accurate measurement of the reflection coefficient. The radiation patterns were recorded with the aid of a real-time digital computer. The stored patterns were then processed to yield gain and beam efficiency. It was concluded that it is possible to design a highly efficient antenna for radiometer use and to measure its parameters precisely. However, it was found that it is necessary to modify the conventional definition of beamwidth somewhat if this term is to be meaningful for radiometer applications.
Caldecott, R.↗
Effects of positive ion implantation into antireflection coating of silicon solar cells
The state of technological development of Si solar cells for highest obtained efficiency and radiation resistance is summarized. The various theoretical analyses of Si solar cells are reviewed. It is shown that factors controlling blue response are carrier diffusion length, surface recombination, impurity concentration profile in surface region, high level of surface impurity concentration (degeneracy), reflection coefficient of oxide, and absorption coefficient of Si. The theory of ion implantation of charge into the oxide antireflection coating is developed and side effects are discussed. The experimental investigations were directed at determining whether the blue response of Si solar cells could be improved by phosphorus ion charges introduced into the oxide antireflection coating.
Middleton, A. E.↗
A noncoherent model for microwave emissions and backscattering from the sea surface
The two-scale (small irregularities superimposed upon large undulations) scattering theory proposed by Semyonov was extended and used to compute microwave apparent temperature and the backscattering cross section from ocean surfaces. The effect of the small irregularities upon the scattering characteristics of the large undulations is included by modifying the Fresnel reflection coefficients; whereas the effect of the large undulations upon those of the small irregularities is taken into account by averaging over the surface normals of the large undulations. The same set of surface parameters is employed for a given wind speed to predict both the scattering and the emission characteristics at both polarizations.
Wu, S. T.↗
Scattering of electromagnetic waves from a turbulent plasma slab.
Scattering of electromagnetic waves from a turbulent plasma slab is studied. Part of the effects of the multiple scattering is taken into account. The reflection coefficient is found to be increased and its variation with respect to the slab thickness is smoothed out by the random scattering.
Liu, C. H.↗