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Results for “ELECTROMAGNETIC WAVE”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 541 records · Page 30

Fluid mechanics of meteor trails

Meteor ionized trails initial expansion and diffusion resulting in dissociation and ionization of air molecules through collision, using electromagnetic wave scattering

Liu, V. C.↗

Random operator equations in mathematical physics. I

Stochastic differential equations objectives, limitations and restrictive assumptions in physical problems, discussing electromagnetic wave propagation in random continuum or random dAlembertian operator

Adomian, G.↗

Van Allen belt plasma physics

Plasma turbulence in Van Allen belts, examining weak turbulent electromagnetic wave properties, with emphasis on trapped energetic particles radiation

Kennel, C. F.↗

Optical mixing in a magnetoactive plasma

Homogeneous plasma electrostatic oscillations excitation by electromagnetic waves nonlinear interaction in magnetic field, deriving expression for density perturbation

Weyl, G.↗

Scattering from rough surfaces

Electromagnetic wave scattering from rough surfaces, discussing radar return differences for different polarizations

Moore, R. K.↗

Redirecting electromagnetic beams through wide angles

Electromagnetic wave enters reflector array consisting of grid work of metallic reflectors with each reflector obscuring a portion of its neighbors to prevent direct passage of wave through grid. Antenna movement involves reduced amplitude of angular motion and internal concellations of translational and rotational inertias.

Dimeff, J.↗

Theoretical frameworks for testing relativistic gravity: A review

Metric theories of gravity are presented, including the definition of metric theory, evidence for its existence, and response of matter to gravity with test body trajectories, gravitational red shift, and stressed matter responses. Parametrized post-Newtonian framework and interpretations are reviewed. Gamma, beta and gamma, and varied other parameters were measured. Deflection of electromagnetic waves, radar time delay, geodetic gyroscope precession, perihelion shifts, and periodic effects in orbits are among various studies carried out for metric theory experimentation.

Thorne, K. S.↗

A computer program to evaluate optical systems

A computer program is used to evaluate a 25.4 cm X-ray telescope at a field angle of 20 minutes of arc by geometrical analysis. The object is regarded as a point source of electromagnetic radiation, and the optical surfaces are treated as boundary conditions in the solution of the electromagnetic wave propagation equation. The electric field distribution is then determined in the region of the image and the intensity distribution inferred. A comparison of wave analysis results and photographs taken through the telescope shows excellent agreement.

Innes, D.↗

Laser amplification in an inhomogeneous plasma

The propagation of an electromagnetic wave into an inhomogeneous plasma was studied. In a plasma with large density gradients a QTX mode propagating perpendicular to the magnetic field can encounter a resonance and a cutoff separated by a distance comparable to the incident wave length. In this region the wave is evanescent, and in general there will be a reflected and transmitted wave, and amplification will occur in the region near the resonance. The amplification is important for the study of nonlinear phenomena and for feedback stabilization applications.

White, R.↗

Electromagnetic scattering by arbitrarily oriented ice cylinders.

The scattering of electromagnetic waves by arbitrarily oriented, infinitely long circular cylinders is solved by following the procedures outlined by van de Hulst. The far-field intensities for two cases of a linearly polarized incident wave are derived. The scattering coefficients involve the Bessel functions of the first kind, the Hankel functions of the second kind, and their first derivatives. Calculations are made for ice cylinders at three wavelengths: 0.7, 3, and 10 microns. The numerical results of intensity coefficients are presented as functions of the observation angle. A significant cross-polarized component for the scattered field, which vanishes only at normal incidence, is obtained. It is also shown that the numerous interference maxima and minima of the intensity coefficients due to single-particle effects depend on the size parameter as well as on the oblique incident angle.

Liou, K.-N.↗