Quantum optics or quantum electronics.
Quantum optics or electronics, discussing electromagnetic waves control and interactions with matter, maser oscillators theory and characteristics, nonlinear optics, induced transparency, etc
Townes, C. H.↗
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Results for “ELECTROMAGNETIC INTERACTIONS”
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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Classical laser.
In this paper a completely classical model for laser action is discussed. An active medium consisting of classical anharmonic oscillators interacts with a classical electromagnetic field in a resonant cavity. Comparison with the case of a medium consisting of harmonic oscillators shows the significance of nonlinearities for producing self-sustained oscillations in the radiation field. The results for the classical model are found to be similar to those for a semiclassical model of the ammonia-beam maser. The conclusion is that laser action is not intrinsically a quantum-mechanical effect. The classical-laser theory as given in this paper can also be applied to the case of the electron-cyclotron maser.
Borenstein, M.↗
Multi-Satellite Attitude Prediction program/Orbiting Solar Observatory-8 (MSAP/OSO-8) operating guide
The sun's lower corona and chromosphere and their interaction in the X-ray and ultraviolet (UV) spectral regions were investigated to better understand the transport of energy from the photosphere to the corona. The interaction between the solar electromagnetic and particle radiation and the earth's environment was studied and the background component of cosmic X-rays was discussed.
Tate, V. H.↗
Fast electrons in small solar flares
This review summarizes both the direct spacecraft observations of nonrelativistic solar electrons, and observations of the X-ray and radio emission generated by these particles at the sun and in the interplanetary medium. These observations bear on the basic astrophysical process of particle acceleration in tenuous plasmas. We find that in many small solar flares, the nearly 5-100 keV electrons accelerated during flash phase constitute the bulk of the total flare energy. Thus the basic flare mechanism in these flares essentially converts the available flare energy into fast electrons. These electrons may produce the other flare electromagnetic emissions through their interactions with the solar atmosphere. In large proton flares these electrons may provide the energy to eject material from the sun and to create a shock wave which could accelerate nuclei and electrons to much higher energies.
Lin, R. P.↗
Lightning Technology: Proceedings of a Technical Symposium
Several facets of lightning technology are considered including phenomenology, measurement, detection, protection, interaction, and testing. Lightning electromagnetics, protection of ground systems, and simulated lightning testing are emphasized. The lightning-instrumented F-106 aircraft is described.
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Conservation laws for relativistic guiding-center plasma
A covariant relativistic formulation is used for self-consistent dynamics of a guiding-center plasma in an electromagnetic field. The reciprocal interactions appear as a magnetization in Maxwell's equations and as field gradient forces in the guiding-center dynamical equation. The ten local conservation laws corresponding to translational and rotational invariance of the Minkowski space are expressed in terms of a symmetric energy-momentum tensor.
Similon, P. L.↗
The theory of ionospheric focused heating
Ionospheric modification by high power radio waves and by chemical releases are combined in a theoretical study of ionospheric focused heating. The release of materials which promote electron-ion recombination creates a hole in the bottomside ionosphere. The ionospheric hole focuses high power radio waves from a ground-based transmitter to give a 20 dB or greater enhancement in power density. The intense radio beam excites atomic oxygen by collisions with accelerated electrons. Airglow from the excited oxygen provides a visible trace of the focused beam. The large increase in the intensity of the radio beam stimulates new wave-plasma interactions. Numerical simulations show that the threshold for the two-plasmon decay instability is exceeded. The interaction of the pump electromagnetic wave with the backward plasmon produces a scattered electromagnetic wave at 3/2 the pump frequency. The scattered wave provides a unique signature of the two-plasmon decay process for ground-based detection.
Bernhardt, P. A.↗
Plasma flow processes within magnetic nozzle configurations
An attempt is made to separate the interactive processes occurring in electromagnetic devices and to examine the acceleration of ionized gas within magnetic fields which can guide it through an expansion process. The plasma was generated in a single turn coil 50 cm long with a radius of 5.25 cm which surrounded a quartz tube with an internal radius of 3.81 cm and a length of 100 cm. Choking was found to occur at both sonic and cusp velocities which were coincident in the present experiment.
York, Thomas M.↗
Fireballs
The sudden release of copiuos gamma-ray photons into a compact region creates an opaque photon-lepton fireball due to the prolific production of electron-positron pairs. The photons that we observe in the bursts emerge only at the end of the fireball phase after it expanded sufficiently to become optically thin or after it converted its energy to the kinetic energy of relativistic baryons which convert it, in turn, to electromagnetic pulse via the interaction with interstellar matter. It is essential, therefore, to analyze the eveolution of a fireball in order to comprehend the observed features of gamma-ray bursts. We discuss various aspects of fireball hydrodynamics and the resulting emitted spectra.
Piran, Tsvi↗
A Science Strategy for Space Physics
This report by the Committee on Solar and Space Physics and the Committee on Solar-Terrestrial Research recommends the major directions for scientific research in space physics for the coming decade. As a field of science, space physics has passed through the stage of simply looking to see what is out beyond Earth's atmosphere. It has become a 'hard' science, focusing on understanding the fundamental interactions between charged particles, electromagnetic fields, and gases in the natural laboratory consisting of the galaxy, the Sun, the heliosphere, and planetary magnetospheres, ionospheres, and upper atmospheres. The motivation for space physics research goes far beyond basic physics and intellectual curiosity, however, because long-term variations in the brightness of the Sun virtually affect the habitability of the Earth, while sudden rearrangements of magnetic fields above the solar surface can have profound effects on the delicate balance of the forces that shape our environment in space and on the human technology that is sensitive to that balance. The several subfields of space physics share the following objectives: to understand the fundamental laws or processes of nature as they apply to space plasmas and rarefied gases both on the microscale and in the larger complex systems that constitute the domain of space physics; to understand the links between changes in the Sun and the resulting effects at the Earth, with the eventual goal of predicting the significant effects on the terrestrial environment; and to continue the exploration and description of the plasmas and rarefied gases in the solar system.
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Time-Dependent Traveling Wave Tube Model for Intersymbol Interference Investigations
For the first time, a computational model has been used to provide a direct description of the effects of the traveling wave tube (TWT) on modulated digital signals. The TWT model comprehensively takes into account the effects of frequency dependent AM/AM and AM/PM conversion, gain and phase ripple; drive-induced oscillations; harmonic generation; intermodulation products; and backward waves. Thus, signal integrity can be investigated in the presence of these sources of potential distortion as a function of the physical geometry of the high power amplifier and the operational digital signal. This method promises superior predictive fidelity compared to methods using TWT models based on swept-amplitude and/or swept-frequency data. The fully three-dimensional (3D), time-dependent, TWT interaction model using the electromagnetic code MAFIA is presented. This model is used to investigate assumptions made in TWT black-box models used in communication system level simulations. In addition, digital signal performance, including intersymbol interference (ISI), is compared using direct data input into the MAFIA model and using the system level analysis tool, SPW.
Kory, Carol L.↗
Intersymbol Interference Investigations Using a 3D Time-Dependent Traveling Wave Tube Model
For the first time, a physics based computational model has been used to provide a direct description of the effects of the TWT (Traveling Wave Tube) on modulated digital signals. The TWT model comprehensively takes into account the effects of frequency dependent AM/AM and AM/PM conversion; gain and phase ripple; drive-induced oscillations; harmonic generation; intermodulation products; and backward waves. Thus, signal integrity can be investigated in the presence of these sources of potential distortion as a function of the physical geometry of the high power amplifier and the operational digital signal. This method promises superior predictive fidelity compared to methods using TWT models based on swept amplitude and/or swept frequency data. The fully three-dimensional (3D), time-dependent, TWT interaction model using the electromagnetic code MAFIA is presented. This model is used to investigate assumptions made in TWT black box models used in communication system level simulations. In addition, digital signal performance, including intersymbol interference (ISI), is compared using direct data input into the MAFIA model and using the system level analysis tool, SPW (Signal Processing Worksystem).
Kory, Carol L.↗
Probing the Intergalactic Magnetic Field with the Anisotropy of the Extragalactic Gamma-Ray Background
The intergalactic magnetic field (IGMF) may leave an imprint on the anisotropy properties of the extragalactic gamma-ray background, through its effect on electromagnetic cascades triggered by interactions between very high energy photons and the extragalactic background light. A strong IGMF will deflect secondary particles produced in these cascades and will thus tend to isotropize lower energy cascade photons, thus inducing a modulation in the anisotropy energy spectrum of the gamma-ray background. Here we present a simple, proof-of-concept calculation of the magnitude of this effect and demonstrate that the two extreme cases (zero IGMF and IGMF strong enough to completely isotropize cascade photons) would be separable by ten years of Fermi observations and reasonable model parameters for the gamma-ray background. The anisotropy energy spectrum of the Fermi gamma-ray background could thus be used as a probe of the IGMF strength.
Venters, T. M.↗
Probing the Intergalactic Magnetic Field with the Anisotropy of the Extragalactic Gamma-ray Background
The intergalactic magnetic field (IGMF) may leave an imprint on the angular anisotropy of the extragalactic gamma-ray background through its effect on electromagnetic cascades triggered by interactions between very high energy photons and the extragalactic background light. A strong IGMF will deflect secondary particles produced in these cascades and will thus tend to isotropize lower energy cascade photons, thereby inducing a modulation in the anisotropy energy spectrum of the gamma-ray background. Here we present a simple, proof-of-concept calculation of the magnitude of this effect and demonstrate that current Fermi data already seem to prefer nonnegligible IGMF values. The anisotropy energy spectrum of the Fermi gamma-ray background could thus be used as a probe of the IGMF strength.
anisotrophy↗
Mixing the Solar Wind Proton and Electron Scales: Effects of Electron Temperature Anisotropy on the Oblique Proton Firehose Instability
The double adiabatic expansion of the nearly collisionless solar wind plasma creates conditions for the firehose instability to develop and efficiently prevent the further increase of the plasma temperature in the direction parallel to the interplanetary magnetic field. The conditions imposed by the firehose instability have been extensively studied using idealized approaches that ignore the mutual effects of electrons and protons. Recently, more realistic approaches have been proposed that take into account the interplay between electrons and protons, unveiling new regimes of the parallel oscillatory modes. However, for oblique wave propagation the instability develops distinct branches that grow much faster and may therefore be more efficient than the parallel firehose instability in constraining the temperature anisotropy of the plasma particles. This paper reports for the first time on the effects of electron plasma properties on the oblique proton firehose (PFH) instability and provides a comprehensive vision of the entire unstable wave-vector spectrum, unifying the proton and the smaller electron scales. The plasma β and temperature anisotropy regimes considered here are specific for the solar wind and magnetospheric conditions, and enable the electrons and protons to interact via the excited electromagnetic fluctuations. For the selected parameters, simultaneous electron and PFH instabilities can be observed with a dispersion spectrum of the electron firehose (EFH) extending toward the proton scales. Growth rates of the PFH instability are markedly boosted by the anisotropic electrons, especially in the oblique direction where the EFH growth rates are orders of magnitude higher.
plasmas↗
Chip-based droplet sorting
A non-contact system for sorting monodisperse water-in-oil emulsion droplets in a microfluidic device based on the droplet's contents and their interaction with an applied electromagnetic field or by identification and sorting.
42 ENGINEERING↗
Chip-based droplet sorting
A non-contact system for sorting monodisperse water-in-oil emulsion droplets in a microfluidic device based on the droplet's contents and their interaction with an applied electromagnetic field or by identification and sorting.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Electromagnetic field-assisted method for chemical conversion
Embodiments relate to methods for enhancing chemical conversions. One or more embodiments relate to a method for enhancing a multi-step chemical conversion reaction. The method includes providing a reactant mixture comprising one or more reacting specie(s); and providing a catalyst or sorbent comprising one or more support materials and one or more deposited catalytically active materials. The method further includes applying an electromagnetic field with a prescribed power, frequency, and pulsing strategy specific to interactions of reactant species and an electromagnetic field with at least one of the support materials, sorbent, and catalytically active materials in a particular chemical reaction.
Shekhawat, Dushyant↗