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Magnetic field-aligned particle precipitation
Magnetic field-aligned particle fluxes are a common auroral phenomenon. Precipitating field-aligned electrons are seen in the vicinity of auroral arcs as suprathermal bursts, as well as superimposed on the more isotropic inverted V electron precipitation. Electron distribution functions reveal two distinct source populations for the inverted V and field-aligned electron components, and also suggest possible acceleration mechanisms. The inverted V electrons are a hot, boundary plasma sheet population that gains the full parallel acceleration. The field-aligned component appears to originate from cold ionospheric electrons that may be distributed throughout the acceleration region. A turbulent parallel field might explain the apparent lifetime of cold electrons in the acceleration region.
Report of particles and fields working group
Magnetic and electric fields, solar particles, galactic cosmic rays, radio propagation, and other atmospheric conditions encountered during lunar explorations
Catalog of particles and fields data 19581965
Available particles and fields data, covering the period 1966 to 1973 inclusive, are announced. Most data result from individual experiments carried on board individual spacecraft. A variety of user-oriented data are included. A newly created composite interplanetary magnetic field data set is discussed and other data products, that may interest the particles/fields community are mentioned, including geomagnetism, magnetopause and bow shock positions, and magnetospherically trapped particles.
Heliospheric energetic particle transport: Analysis of near-field-aligned particle propagation for SEP events observed by Wind and MAVEN
Magnetic field alignments of spacecraft over large distances in the heliosphere are rare and are usually very limited in duration. Cruise phases of planetary transfers, however, are an exception to this rule, given the Hohmann-Parker effect. The transfer of the MAVEN s/c in 2014 is one such example. Multiple (~10) solar particle events occurred and were detected at both MAVEN and the Wind s/c, originating from solar activity near the foot points of both s/c. We show initial analysis results of the data collected by the solar wind and energetic particle instruments on both s/c while they were more than 0.2 AU apart, but practically Parker field aligned. Using a 1D model, we present initial simulations in qualitative agreement with energetic electron measurements. Next step is to implement the 2D model with approximate particle release from the Sun, and transport durations between Sun, Earth, and MAVEN. We will discuss implications for this data-model comparison, including the possibility to constrain particle scattering inside 1 AU, as well as its radial dependence between Earth and MAVEN.
Compilation of scientific objective portions of ames research center study contracts on a solar probe and a short report on ''particle and fields experiments for a solar probe''
Design of experiments for solar probe for measuring solar wind, particles, fields, and other interplanetary data
Particles and Fields in the Magnetosphere
Particle fluxes and magnetic fields in magnetosphere
Advances in Particles and Field Research in the Satellite Era
Particles and fields research since 1958 - solar wind effect on earth, radiation belts, earth magnetic field, solar energetic particles and ground effects, cosmic rays, and neutrons
Nasa particles and fields spacecraft
Spacecraft investigation of energetic particles and magnetic fields in space
A review of electron bombardment thruster systems/spacecraft field and particle interfaces
Information on the field and particle interfaces of electron bombardment ion thruster systems was summarized. Major areas discussed were the nonpropellant particles, neutral propellant, ion beam, low energy plasma, and fields. Spacecraft functions and subsystems reviewed were solar arrays, thermal control systems, optical sensors, communications, science, structures and materials, and potential control.
Drift mirror instability in the magnetosphere - Particle and field oscillations and electron heating
Particle and field oscillations and electron heating due to drift mirror instability in magnetosphere
Research in particles and fields
Cosmic ray research and particle and field theory in space are examined. Data also cover experiments designed especially for spacecraft. An extensive bibliography is included.
Advances in particles and field research in the satellite era
Particle and field theory research related to satellites and space probes
Scaling Properties of Particle Density Fields Formed in Simulated Turbulent Flows
Direct numerical simulations (DNS) of particle concentrations in fully developed 3D turbulence were carried out in order to study the nonuniform structure of the particle density field. Three steady-state turbulent fluid fields with Taylor microscale Reynolds numbers (Re(sub lambda)) of 40, 80 and 140 were generated by solving the Navier-Stokes equations with pseudospectral methods. Large scale forcing was used to drive the turbulence and maintain temporal stationarity. The response of the particles to the fluid was parameterized by the particle Stokes number St, defined as the ratio of the particle's stopping time to the mean period of eddies on the Kolmogorov scale (eta). In this paper, we consider only passive particles optimally coupled to these eddies (St approx. = 1) because of their tendency to concentrate more than particles with lesser or greater St values. The trajectories of up to 70 million particles were tracked in the equilibrated turbulent flows until the particle concentration field reached a statistically stationary state. The nonuniform structure of the concentration fields was characterized by the multifractal singularity spectrum, f(alpha), derived from measures obtained after binning particles into cells ranging from 2(eta) to 15(eta) in size. We observed strong systematic variations of f(alpha) across this scale range in all three simulations and conclude that the particle concentration field is not statistically self similar across the scale range explored. However, spectra obtained at the 2(eta), 4(eta), and 8(eta) scales of each flow case were found to be qualitatively similar. This result suggests that the local structure of the particle concentration field may be flow-Independent. The singularity spectra found for 2n-sized cells were used to predict concentration distributions in good agreement with those obtained directly from the particle data. This Singularity spectrum has a shape similar to the analogous spectrum derived for the inertial-range energy dissipation fields of experimental turbulent flows at Re(sub lambda) = 110 and 1100. Based on this agreement, and the expectation that both dissipation and particle concentration are controlled by the same cascade process, we hypothesize that singularity spectra similar to the ones found in this work provide a good characterization of the spatially averaged statistical properties of preferentially concentrated particles in higher Re(sub lambda) turbulent flows.
Research in particles and fields
Investigations, by particle-detectors flown on spacecraft, of the astrophysical aspects of cosmic radiation and the radiation environment of the earth are reported along with the research of the interplanetary medium, and planetary magnetic fields. The cosmic ray interactions with the interplanetary and interstellar medium, and radio scintillation theory were also studied.
Particles and fields subsatellite program
Developments in the Particles and Fields Lunar Subsatellite Program are reported. The basic purpose of the program is to provide three subsatellites with one for launch with Apollo 15, and one for launch with Apollo 16. At this time all three subsatellites have been completed except for a few minor changes, and the Flight 1 subsatellite has been successfully placed in orbit for the Apollo 15 CSM with all systems performing satisfactorily. The Flight 2 subsatellite is scheduled for launch on March 17, 1972. The Qualification Unit subsatellite has successfully completed its qualification testing.
Particle and fields experiments for a solar probe
Solar probe experiments for studying propagation mechanism of solar energy and structure of particle fields
FIELDS AND PARTICLES EXPERIMENTS ON MARINER II
Interplanetary medium - fields and particles data from mariner ii venus probe