Microscale fluctuations in the solar wind

Theoretical constraints on the interpretation of fluctuations (either propagating or stationary) in the interplanetary medium are reviewed, with emphasis on the important differences between the properties of hydromagnetic waves (and stationary structures) in collisionless and in collision-dominated plasmas, and on the possible roles of Landau damping and nonlinear effects in determining the interplanetary fluctuation spectrum. Hypotheses about the origins of the fluctuations and their influence on the large-scale properties of the solar wind are reviewed

Model for energy transfer in the solar wind: Formulation of model

The two-fluid solar-wind model is extended by including the collisionless dissipation of hydromagnetic waves originating at the sun. A series of solar wind models is generated, parameterized by the total energy flux of hydromagnetic waves at the base of the model. The resulting properties of propagation and dissipating of hydromagnetic waves on this model are presented

A survey of laser lightning rod techniques

The work done to create a laser lightning rod (LLR) is discussed. Some ongoing research which has the potential for achieving an operational laser lightning rod for use in the protection of missile launch sites, launch vehicles, and other property is discussed. Because of the ease with which a laser beam can be steered into any cloud overhead, an LLR could be used to ascertain if there exists enough charge in the clouds to discharge to the ground as triggered lightning. This leads to the possibility of using LLRs to test clouds prior to launching missiles through the clouds or prior to flying aircraft through the clouds. LLRs could also be used to probe and discharge clouds before or during any hazardous ground operations. Thus, an operational LLR may be able to both detect such sub-critical electrical fields and effectively neutralize them

Real-time data compression of broadcast video signals

A non-adaptive predictor, a nonuniform quantizer, and a multi-level Huffman coder are incorporated into a differential pulse code modulation system for coding and decoding broadcast video signals in real time

Situation Report on Simplified Forage Harvesters

Fsrm interest is centered primarily on their relatively low cost and versatility. Other considerations include their operating characteristics and power requirements as well as the kind of product produced

Salt budget in the Lake Washington ship canal system

Salt water enters the freshwater system of Lake Washington, Montlake Canal, Lake Union, Fremont Canal, and Salmon Bay through the U.S. Government Locks at Ballard…

Comparison of the beta-alpha angular correlations in the Li8 and B8 beta decays, and the conserved vector current theory

This paper describes a comparison of the beta-alpha angular correlations of the beta decays of Li8 and B8 to the 2.90-Mev alpha-unstable level of Be8. The data were fitted to an angular correlation in the laboratory system of the form W(θβα)=1+Acosθβα+Bcos2θβα, where A and B were independently determined for the Li8 and B8 beta decays from measurements at θβα=0°, 90°, and 180°. The coefficients A are due to the recoil of Be8* and have the same sign for both beta decays. The coefficients B arise from the interference of forbidden vector matrix elements with the allowed axial vector matrix element and have different signs in the two decays. The correlation for the Li8 decay was measured with average total beta energies, Wβ~5, 8, and 11 Mev. Both A and B were found to be approximately linear in Wβ. The correlation for the B8 decay was measured only with average Wβ~11 Mev. From the data with Wβ~11 Mev, the difference of the coefficients, B(Li8)-B(B8), equals (0.0070±0.0012)Wβ. This result is compared with theoretical predictions based on the older Fermi and the newer conserved vector current theories of beta decay. The experiment agrees with the prediction of the latter theory

Outskirts of Nearby Disk Galaxies: Star Formation and Stellar Populations

The properties and star formation processes in the far-outer disks of nearby spiral and dwarf irregular galaxies are reviewed. The origin and structure of the generally exponential profiles in stellar disks is considered to result from cosmological infall combined with a non-linear star formation law and a history of stellar migration and scattering from spirals, bars, and random collisions with interstellar clouds. In both spirals and dwarfs, the far-outer disks tend to be older, redder and thicker than the inner disks, with the overall radial profiles suggesting inside-out star formation plus stellar scattering in spirals, and outside-in star formation with a possible contribution from scattering in dwarfs. Dwarf irregulars and the far-outer parts of spirals both tend to be gas dominated, and the gas radial profile is often non-exponential although still decreasing with radius. The ratio of H-alpha to far-UV flux tends to decrease with lower surface brightness in these regions, suggesting either a change in the initial stellar mass function or the sampling of that function, or a possible loss of H-alpha photons.Comment: 20 pages, 8 figures, Invited review, Book chapter in "Outskirts of Galaxies", Eds. J. H. Knapen, J. C. Lee and A. Gil de Paz, Astrophysics and Space Science Library, Springer, in pres

Space Charge Limited 2-d Electron Flow between Two Flat Electrodes in a Strong Magnetic Field

An approximate analytic solution is constructed for the 2-d space charge limited emission by a cathode surrounded by non emitting conducting ledges of width Lambda. An essentially exact solution (via conformal mapping) of the electrostatic problem in vacuum is matched to the solution of a linearized problem in the space charge region whose boundaries are sharp due to the presence of a strong magnetic field. The current density growth in a narrow interval near the edges of the cathode depends strongly on Lambda. We obtain an empirical formula for the total current as a function of Lambda which extends to more general cathode geometries.Comment: 4 pages, LaTex, e-mail addresses: [email protected], [email protected]