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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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Numerical analysis of structure of one-dimensional unsteady magnetic compression waves propagating into collisionless plasma, using motion equations
Based on technologies developed for the Jet Propulsion Laboratory (JPL) Free-Flying-Magnetometer (FFM) concept, we propose to modify the present design of FFMs for detection of mines and arsenals with large magnetic signature.
This project investigated how plasmas interact with energetic particles and solid materials under extreme conditions relevant to fusion energy, space plasmas, and planetary environments. Using experiments on the DIII-D National Fusion Facility, the research first examined how high-energy electrons move, become trapped, and are released in plasmas containing magnetic islands—structures commonly found in fusion reactors and Earth’s magnetosphere—providing new insight into particle transport and acceleration processes. The project also explored plasma-driven chemical reactions that can occur during meteoroid entry into planetary atmospheres, demonstrating that simple molecules such as ammonia can be produced and survive in high-temperature plasma conditions. Together, these results improve understanding of plasma behavior across laboratory, space, and planetary systems while informing fusion plasma control and plasma–material interaction studies. The project additionally contributed to workforce development by training graduate students, undergraduates, and early-career researchers and by disseminating results through peer-reviewed publications and international scientific conferences.
Models of interacting many-body quantum systems that may realize new exotic phases of matter, notably quantum spin liquids, are challenging to study using even state-of-the-art classical methods such as tensor network simulations. Quantum computing provides a promising route for overcoming these difficulties to find ground states, dynamics, and more. In this paper, we argue that recently developed hybrid quantum-classical algorithms based on real-time evolution are promising methods for solving a particularly important model in the search for spin liquids, the antiferromagnetic Heisenberg model on the two-dimensional kagome lattice. We show how to construct efficient quantum circuits to implement time evolution for the model and to evaluate key observables on the quantum computer, and we argue that the method has favorable scaling with increasing system size. We then restrict to a 12-spin star plaquette from the kagome lattice and a related 8-spin system, and we give an empirical demonstration on these small systems that the hybrid algorithms can efficiently find the ground state energy and the magnetization curve. For these demonstrations, we use four levels of approximation: exact state vectors, exact state vectors with statistical noise from sampling, noisy classical emulators, and (for the 8-spin system only) real quantum hardware, specifically the Quantinuum H1-1 processor; for the noisy simulations and hardware demonstration, we also employ error mitigation strategies based on the symmetries of the Hamiltonian. Our results strongly suggest that these hybrid algorithms present a promising direction for studying quantum spin liquids and more generally for resolving important unsolved problems in condensed matter theory and beyond.
Distortion of the earths magnetic field in the radiation belt regions by a combination of the ring current and the solar plasma flow
Sound and ultrasound propagation and absorption along quantized magnetic field
Magnetic and related stars - AAS and NASA Conference, Goddard Space Flight Center, November 1965
Magnetic field measurement in solar prominences and structure in region of chromospheric filaments
Shield facility and Helmholtz coil system used to investigate chronic effects on man of zero magnetic field regulated to cancel geomagnetic field variations
Low density and low viscosity magnetic propellant for use under zero gravity conditions
Photospheric and interplanetary magnetic field polarity and magnitude comparison, using Explorer observations
Radiation cooled MPD thrustor with permanent and superconducting magnets, describing test facilities and measurement techniques for performance tests
Large-scale averages of daily solar magnetograms have been compared by cross-correlation with the interplanetary magnetic sector pattern during a 2.5 yr interval. A significant correlation was found at a lag of about 4.5 days, with the amplitude of the correlation depending on the area included in the magnetogram averages. The highest correlation was found when an area of one quarter of the solar disk was used, which is consistent with the idea that the photospheric features which are to be associated with the interplanetary sector pattern are large scale features.
Electron magnetic resonance spectra of soil samples 14163,68, 14148,31, 14149,47, 14156,31, and 14003,60, and of fragmental rocks 14301,66, 14303,42, 14310,68, 14311,36, 14318,36, and 14321,166 have been recorded at 9 and 35 GHz at 300 K and at 9 GHz at 130 K. One spectral component, the characteristic ferromagnetic resonance, of all the soil samples is 50 to 1000 times more intense than any other component in the soils or in the spectra of the rocks. The intensity of this component in Apollo 11, Apollo 12, and Apollo 14 soils varies only within one order of magnitude. It varies with depth below lunar surface but is not correlated with depth. The intensity does not have any correlation with the fraction of glassy particles nor with the fraction of anorthositic particles.
The hydrodynamic properties of convective motions in a stratified atmosphere suggest that the supergranules in the solar photosphere extend to depths in excess of their horizontal diameters. The calculations presented here show that the weak fields which appear at the photosphere are as strong as, or stronger than, the horizontal fields anywhere in the supergranules below the surface. Hence the general 10 to 100 gauss azimuthal field of the sun, whose presence is indicated by the emerging bipolar magnetic regions, must lie below the base of the supergranules, i.e., below a depth probably of the order of 20,000 to 50,000 km. Presumably then the azimuthal field is generated by nonuniform rotation below the supergranule convection and does not appear in the supergranule layer because of the high rate of turbulent diffusion loss from that layer.
Large and quick changes of the latitude of the interplanetary magnetic field from its southward to northward direction are shown to be associated with the disappearance of the Es-q layer (Knecht, 1959) at the equatorial ionosphere during the daytime or with the reversal of E region horizontal and F region vertical electron drifts during both night and day. This phenomenon is suggested as the imposition of an electric field in the ionosphere in a direction opposite to that of the Sq electric field. The resultant electrostatic field on the equatorial ionosphere would be decreased or even reversed from its normal direction, resulting in the reduction of electron drift velocity. When the normal Sq field is over-compensated by the magnetospheric electric field, the electron drifts are reversed and the irregularities in the E region due to the cross-field instabilities are inhibited, resulting in the sudden disappearance of the Es-q layers.
The elements of the cycle are summarized. The basic advantages include high entropy density in the magnetic material, completely reversible processes, convenient control of the entropy by the applied field, the feature that heat transfer is possible during all processes, and the ability of the ideal cycle to attain Carnot efficiency. The mean field theory is used to predict the entropy of a ferromagnet in an applied field and also the isothermal entropy change and isentropic temperature change caused by applying a field. The results for isentropic temperature change are compared with experimental data on Gd. Coarse mixtures of ferromagnetic materials with different Curie points are proposed to modify the path of the cycle in the T-S diagram in order to improve the efficiency or to increase the specific power.
The spatial organization of the observed photospheric magnetic field as well as its relation to the polarity of the IMF have been studied using high resolution magnetograms from the Kitt Peak National Observatory. Systematic patterns in the large scale field are due to contributions from both concentrated flux and more diffuse flux. The polarity of the photospheric field, determined on various spatial scales, correlates with the polarity of the IMF. Analyses based on several spatial scales in the photosphere suggest that new flux in the interplanetary medium is often due to relatively small photospheric features which appear in the photosphere up to one month before they are manifest at the earth.