The nuclear soft-core potential and cosmic-ray phenomena
Nuclear soft core potential reproduction by isoscalar vector meson in nonlocal field theory of fireball in high energy cosmic ray collisions
Canuto, V.↗
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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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Observations of lunar transient phenomena in the Aristarchus region
Lunar transients in Aristarchus region with respect to tidal, sunrise, illumination, magnetic tail, bow shock and solar activity hypotheses
Cameron, W. S.↗
Observations of auroral hiss, LHR noise, and other phenomena in the frequency range 20 Hz-540 kHz on OGO 6
Ionospheric electric and electromagnetic waves broadband characteristics, investigating auroral hiss and LHR noise
Johnson, W. C.↗
Basic investigation of turbine erosion phenomena
An analytical-empirical model is presented of turbine erosion that fits and explains experience in both steam and metal vapor turbines. Because of the complexities involved in analyzing turbine problems, in a pure scientific sense, it is obvious that this goal can be only partially realized. Therefore, emphasis is placed on providing a useful model for preliminary erosion estimates for given configurations, fluids, and flow conditions.
Pouchot, W. D.↗
Theoretical studies of ionic and atomic impact phenomena
An absorbing sphere model based on the Landau-Zener method was developed for calculating the energy dependence of the total cross sections for the reaction A(+) + B(-) yields A star + B + Delta E, in which A or B may be atomic or molecular species. It was found that the cross sections were highly dependent on the electron detachment energy of B(-). The ionization total cross sections for Ne star (2p5 3s 3P) + Ar were calculated over a large energy range and compared with experiments.
Olson, R. E.↗
Phenomena after meteoroid penetration of a bumper plate
The analysis of hypervelocity impact of particles on a detector in space, with flow and shock penetration through fluid, plastic, and elastic zones was studied. The original paper and computer program on this topic is presented. Improvements in the program for the study of the formation of a cone of debris are discussed. The truncated apex of the cone is at the hole formed by the penetration of an initially spherical rock through a thin plate. A solution for the penetration of the thin plate was sought.
Todd, F. C.↗
Improved fluid dynamics similarity, analysis and verification. Part 5: Analytical and experimental studies of thermal stratification phenomena
The stratification behavior of a contained fluid subjected to transient free convection heat transfer was studied. A rectangular vessel was employed with heat transfer from two opposite walls of the vessel to the fluid. The wall temperature was increased suddenly to initiate the process and was then maintained constant throughout the transient stratification period. Thermocouples were positioned on a post at the center of the vessel. They were adjusted so that temperatures could be measured at the fluid surface and at specific depths beneath the surface. The predicted values of the surface temperature and the stratified layer thickness were found to agree reasonably well with the experimental measurements. The experiments also provided information on the transient centerline temperature distribution and the transient flow distribution.
Winter, E. R. F.↗
Spatial and spectral studies of solar phenomena
Work proceeded simultaneously in four different areas of solar research. These were: (1) assembly and testing of the components of a multiple-slit H alpha spectrograph, (2) simultaneous observations of the wings of the H alpha line with a newly modified filter, (3) analysis of H alpha high resolution observations in conjunction with magnetic field observations obtained at Kitt Peak, and (4) theoretical analysis of the D3 line HeI.
Harvey, K. L.↗
Lee-side flow phenomena on space shuttle configurations at hypersonic speeds. Part 2: Studies of lee-surface heating at hypersonic Mach numbers
Lee surface heating data, obtained at relatively low unit Reynolds numbers at Mach 6 and 19, are discussed with emphasis on the peak heating behavior. Surface pressures measured along the lee meridian of the delta-wing orbiter are presented and analyzed in conjunction with the heating. The effects of nose bluntness and lee surface geometry on the heating are discussed and general guidelines are presented for modifying the lee surface geometry of the shuttle to reduce vortex-induced heating. The application of the wind tunnel results to realistic shuttle flight conditions is discussed.
Hefner, J. N.↗
Ionospheric magnetic phenomena associated with proton flares
The state of the ionosphere above stations in Kazakhstan is examined in connection with the proton flares of 7 July, 28 August, and 2 September 1966. Universal time is used. It is established that a proton flare causes increased radio absorption (the ionization of the D-region is enhanced, and the minimum reflected frequencies decrease). Magnetic storms and ionospheric disturbances are observed on the earth one-and-a-half to two days after some proton flares.
Rudina, M. P.↗
Experimental surface flow patterns and flow-field phenomena of a delta-wing space-shuttle orbiter
Composite photographs of the surface flow and shadowgraphs of the shock wave pattern are presented that depict the hypersonic flow field of a typical delta wing space shuttle orbiter. Results from a wind tunnel test in air are given in side, oblique, and projected plan views for angles of attack from 0 to 60 deg. The tests were conducted at a Mach number of 7.4 and for Reynolds numbers based on body length of 6,000,000 and 9,000,000. The interrelationship is shown for the intersecting bow and wing leading edge waves with the surface flow for angles of attack for which: (1) the leading edge wave is attached, and (2) the leading edge wave is detached.
Cleary, J. W.↗
Visual phenomena induced by cosmic rays and accelerated particles
Experiments, conducted at cyclotrons together with observations by Apollo astronauts, suggest with little doubt that cosmic nuclei interacting with the visual apparatus cause the phenomenon of light flashes seen on translunar and transearth coast over the past four Apollo missions. Other experiments with high and low energy neutrons and a helium ion beam suggest that slow protons and helium ions with a stopping power greater than 10 to the 8th power eV/gram sq cm can cause the phenomenon in the dark adapted eye. It was demonstrated that charged particles induced by neutrons and helium ions can stimulate the visual apparatus. Some approaches to understanding the long term mission effects of galactic cosmic nuclei interacting with man and his nervous system are outlined.
Tobias, C. A.↗
Preliminary examination of Surveyor 3 components for impact phenomena
Two pieces of the Surveyor 3 spacecraft recovered during the Apollo 12 mission were examined for secondary lunar ejecta and micrometeorite impacts. One piece was section E of the aluminum strut; the other was the nickel-coated beryllium television camera mirror.
Hallgren, D. S.↗
Boundary layer transition: A review of theory, experiment and related phenomena
The overall problem of boundary layer flow transition is reviewed. Evidence indicates a need for new, basic physical hypotheses in classical fluid mechanics math models based on the Navier-Stokes equations. The Navier-Stokes equations are challenged as inadequate for the investigation of fluid transition, since they are based on several assumptions which should be expected to alter significantly the stability characteristics of the resulting math model. Strong prima facie evidence is presented to this effect.
Kistler, E. L.↗
Apollo 14 mission report. Supplement 8: Summary of Apollo experiments on launch phase electrical phenomena
An atmospheric electrical field experiment was conducted during Apollo 14 launch to measure the electrical perturbations produced by the space vehicle. The measurements showed the presence of a much stronger electrical field than was expected, and that the disturbance might be caused by a buildup of electrostatic charges in the launch vehicle engine exhaust clouds, charge buildup of the vehicle itself, or a combination of both. Efforts were also made to establish the origin and carriers of the charge.
Source record↗
Instrumentation for the measurement of high energy phenomena on NASA spacecraft.
High energy astrophysical observations will be conducted primarily from the Small Astronomy Satellites (SAS) and the High Energy Astronomy Observatories (HEAO). The first satellite (SAS A) will carry a set of collimated proportional counters to conduct a high sensitivity, high spatial resolution, all sky survey for X-ray sources. The objective of SAS B will be to search for celestial gamma-ray sources and regions and to measure the flux and energy spectrum of any sources located. A wire grid digitized spark chamber will be the prime detection instrument. The instrumentation of SAS C will consist of modulation collimators, slot collimators, and proportional counters.
Opp, A. G.↗
Pulsation phenomena observed in long-duration vlf whistler-mode signals.
Whistler-mode signals from station NAA (14.7 and 17.8 kHz), Cutler, Maine, show periodic fluctuations (?pulsations') in amplitude and bandwidth. The data were recorded at Eights station, Antarctica, during unmodulated (?key-down') transmissions from NAA lasting up to 2 min. In three of four instances, the pulsations consist of a series of moderate enhancements of the amplitude and bandwidth of the signal, each pulsation lasting about 50 msec. The fourth instance, however, was unusual in that the key-down signal exhibited remarkably regular and intense amplitude variations. In all four occurrences, the period of the pulsation was in the range from 0.3 to 0.6 sec. In three occurrences, this period was roughly the same as the one-hop whistler-mode delay along the field-line path; however, no demonstrable mechanism to explain this association could be found. An explanation of pulsations in terms of multipath fading effects could not be supported by the data. More likely explanations include intrinsic oscillation in the emission generation mechanism, natural oscillation in the energetic-particle population, or modulation of the VLF growth rate by Pc 1 micropulsations in the region of wave growth.
Bell, T. F.↗
A method of computing periods of cyclic phenomena.
Use of an analysis of Expected Mean Square Deviations to search for periodicities in an observational data sample is described. The statistic for testing the null hypothesis of nonperiodicity is derived from a partitioning of the total sum of squared deviations from the mean. Unlike most existing methods, the present one does not require equally spaced observations. No assumptions are made concerning the statistical nature of spacing intervals. The method is illustrated by numerical examples.
Jurkevich, I.↗