Small‐Scale and Mesoscale Variabilities in the Electric Field and Particle Precipitation and Their Impacts on Joule Heating
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Qingyu Zhu↗
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Generation of flow fields in particle fueled combustion systems Technical note no. 1
Dynamic properties of explosion in medium consisting of condensed phase fuel particles dispersed in gaseous oxidizer
GAS PHASE↗
Particles and fields
Interplanetary magnetic field, magnetosphere, solar energetic protons, and galactic cosmic rays
MAGNETOSPHERE↗
Particles and fields - Significant achievements.
Cosmic ray, solar wind and magnetosphere physics discoveries from 1964-1965 space observations
Opp, A. G.↗
Application of the multiple satellite concept to particles and fields research
Four satellite cluster laboratory in near-earth environment to investigate solar-terrestrial relationships, emphasizing interaction of solar wind and magnetosphere
Lysdale, C. A.↗
The particles and fields subsatellite magnetometer experiment
A preliminary analysis of magnetometer data from Apollo 15 subsatellite is concluded. Remanent magnetization is a characteristic property of the moon, and the distribution is such that a complex pattern is produced. A mapping of the distribution is feasible with the present experiment. Lunar induction fields produced by transients in interplanetary magnetic field are detectable at satellite orbit. Magnetometer data will provide estimates of the latitude and longitude dependences of interior conductivity. The plasma void extends to some altitude below the satellite orbit and probably the lunar surface. Solar wind near the limbs is usually strongly disturbed.
Coleman, P. J., Jr.↗
Particle and field observations from Explorer 45 during the December 1971 magnetic storm period
Simultaneous observations are presented from the S3-A (Explorer 45) satellite of the magnetic signature of the ring current and complete measurements of the proton ring current to distances of 5.24 R sub E during the double magnetic storm of 16 to 19 December 1971.
Hoffman, R. A.↗
Particle and field observations from Explorer 45 during the December 1971 magnetic storm period.
Measurements of magnetic field variations and proton energy densities on Explorer 45 during the double magnetic storm of Dec. 16 through 19, 1971. Data are given for the magnetic signature of the ring current and for the proton ring current up to distances of 5.24 earth radii. Diagrams are included for orbits 99, 101, 102, and 103.
Hoffman, R. A.↗
Apollo particles and fields subsatellite magnetometer experiment
The results of the Apollo 15 subsatellite magnetometer experiment are reported. The magnetometer is described including the operation, and specifications. Orbit plots presented are altitude versus time, selenographic longitude versus latitude, and the ecliptic projection of the earth-moon system. The lunar magnetic field, solar wind interaction with the moon, the transfer function of the moon, and the plasma sheet interaction with the moon are discussed.
Coleman, P. J., Jr.↗
Particles and fields in the outer solar system
Use of the MJS77 and MJU missions to perform on site studies of the outer heliosphere and the local interstellar medium is discussed. Subjects for investigation are described, including fluctuations and instabilities of the solar wind in the outer solar system, profiles of the interstellar medium, and interactions between the solar wind and the interstellar medium. On site studies of interstellar cosmic rays are proposed, in particular obtaining interstellar spectra of cosmic ray nuclei and electrons and determining the cosmic-ray modulation region of the heliosphere. The general goals and requirements of the MJS77 and MJU missions are outlined.
Vogt, R. E.↗
Coordinated ionospheric and magnetospheric observations from the ISIS 2 satellite by the ISIS 2 experimenters. Volume 3: High-latitude charged particle, magnetic field and ionospheric plasma observations during northern summer
A list of ISIS 2 experiments and a description of the satellite are presented. Instrumentation of the satellite included an auroral scanning photometer, a red line photometer, a swept frequency sounder, an ion mass spectrometer, and triaxial fluxgate magnetometer. Data format descriptions are provided. Included with the geophysical data set is a list of all passes.
Source record↗
Research in particles and fields
Cosmic rays and astrophysical plasmas, NASA spacecraft experiment activities, and gamma rays are discussed.
Vogt, R. E.↗
Satellite observations of new particle and field signatures associated with SAR arc field lines at magnetospheric heights
Enhancements in thermal ion densities, an oxygen dominated ring current at energies below 17 keV, and invariant latitude-limited bands of intense ELF hiss have been discovered on Stable Auroral Red (SAR) arc field lines at magnetospheric heights. These new signatures were revealed by an examination of 31 coordinated data sets taken simultaneously at magnetospheric and ionospheric heights by the De-1 and -2 satellites during SAR arc traversals within the period September 1981 through April 1982. Data sets from DE-2, for the first time, provide information on the location of a SAR arc (determined by the F region electron temperature enhancement) during the nearly simultaneous passage of these field lines by DE-1 in the magnetosphere. These new high altitude signatures are examined in the context of possible magnetospheric SAR arc energy source mechanisms.
Kozyra, J. U.↗
Preliminary calibration plan for the Advanced Particles and Field Observatory (APAFO) magnetometer experiment
Prelaunch and postlaunch calibration plans for the APAFO magnetometer experiment are presented. A study of tradeoffs between boom length and spacecraft field is described; the results are summarized. The prelaunch plan includes: calibration of the Vector Fluxgate Magnetometer (VFM), Star Sensors, and Scalar Helium Magnetometer (SHM); optical bench integration; and acquisition of basic spacecraft field data. Postlaunch calibration has two phases. In phase one, SHM data are used to calibrate the VFM, total vector magnetic field data are used to calibrate a physical model of the spacecraft field, and both calibrations are refined by iteration. In phase two, corrected vector data are transformed into geocentric coordinates, previously undetected spacecraft fields are isolated, and initial geomagnetic field models are computed. Provided the SHM is accurate to the required 1.0 nT and can be used to calibrate the VFM to the required 3.0- nT accuracy, the tradeoff study indicates that a 12 m boom and a spacecraft field model uncertainty of 5 percent together allow the 1.0 nT spacecraft field error requirement to be met.
Voorhies, C. V.↗
A self-consistent model for the particles and fields upstream of an outgassing comet. I - Gyrotropic and isotropic ion distributions
The magnetic field and solar wind flow parameters in the vicinity of a weakly outgassing comet are determined using a self-consistent model which treats the cometary ions kinetically. Two different assumptions are made concerning the cometary ion distribution function; the pickup cometary ions from either a velocity space gyrotropic ring distribution or a velocity space isotropic shell distribution in the solar wind frame of reference. The individual currents due to the solar wind and cometary ions, which determine the magnetic field, are calculated in each case. Using theoretically determined parameters which reflect the conditions expected to comet Kopff (a typical short-period comet and one possible target for the future CRAF/Cassini mission) for various heliocentric distances, the way in which global field and flow characteristics are influenced by the nature of the cometary ion distribution function is determined.
Flammer, K. R.↗
A self-consistent model for the particles and fields upstream of an outgassing comet. II - A time-dependent description
In a previous paper, the global variation of the magnetic field and solar wind flow parameters in the unshocked region upstream of an outgassing comet was determined using a kinetic treatment for the cometary ions. Two different assumptions were made concerning the cometary ion distribution function: the pickup cometary ions formed either a velocity space gyrotropic ring distribution or a velocity space isotropic shell distribution in the solar wind frame of reference. In the present paper the general case is considered wherein the newly picked up ions are elastically pitch angle scattered from the initial ring distribution to a shell with some characteristic time scale. Using theoretically determined parameters which reflect the conditions expected at Comet Kopff (a typical short-period comet and a possible target for the CRAF/Cassini mission) for various heliocentric distances, how the pitch angle scattering rate affects the global morphology is determined.
Flammer, K.↗
Simultaneous mapping of the unsteady flow fields by Particle Displacement Velocimetry (PDV)
Current experimental and computational techniques must be improved in order to advance the prediction capability of the longitudinal vortical flows shed by underwater vehicles. The generation, development, and breakdown mechanisms of the shed vortices at high Reynolds numbers are not fully understood. The ability to measure hull separated vortices associated with vehicle maneuvering does not exist at present. The existing point-by-point measurement techniques can only capture approximately the large 'mean' eddies but fail to meet the dynamics of small vortices during the initial stage of generation. A new technique, which offers a previously unavailable capability to measure the unsteady cross-flow distribution in the plane of the laser light sheet, is called Particle Displacement Velocimetry (PDV). PDV consists of illuminating a thin section of the flowfield with a pulsed laser. The water is seeded with microscopic, neutrally buoyant particles containing imbedded fluorescing dye which responds with intense spontaneous fluorescence with the illuminated section. The seeded particles in the vortical flow structure shed by the underwater vehicle are illuminated by the pulse laser and the corresponding particle traces are recorded in a single photographic frame. Two distinct approaches were utilized for determining the velocity distribution from the particle traces. The first method is based on matching the traces of the same particle and measuring the distance between them. The direction of the flow can be identified by keeping one of the pulses longer than the other. The second method is based on selecting a small window within the image and finding the mean shift of all the particles within that region. The computation of the auto-correlation of the intensity distribution within the selected sample window is used to determine the mean displacement of particles. The direction of the flow is identified by varying the intensity of the laser light between pulses. Considerable computational resources are required to compute the auto-correction of the intensity distribution. Parallel processing will be employed to speed up the data reduction. A few examples of measured unsteady vortical flow structures shed by the underwater vehicles will be presented.
Huang, Thomas T.↗