Correlated electron and X ray measurements of quiet time electron precipitation: a comparative study of Bremsstrahlung production and transport in the atmosphere

Gaines, E E; Imhof, W L; Francis, W E; Walt, M; Rosenberg, T J

doi:10.1029/JA091iA12p13455

Title: Correlated electron and X ray measurements of quiet time electron precipitation: a comparative study of Bremsstrahlung production and transport in the atmosphere

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Abstract

Five cases of X ray observations from balloons coordinated with measurements of precipitating electrons were obtained during passes of the polar-orbiting satellite P78-1 near Siple, Antarctica (L--4.1), the launch point of the balloons. The observations, made during a geomagnetically quiet period in late December 1980 to early January 1981, showed small enhancements of the X ray fluxes (E>25 keV) and moderate trapped electron fluxes (E>68 keV) with pitch angle distributions extending into the edge of the loss cone sufficient to produce the approx. <0.5 dB of cosmic noise absorption recorded by the Siple 30-MHz riometer. Bremsstrahlung production and transport in the atmosphere were calculated using the measured electron fluxes, energy spectra, and pitch angle distributions for the source. The X ray fluxes and spectra calculated for the balloon altitudes were in good agreement with those measured from the balloons when the total energy deposition from electrons, E>10 keV, exceeded 2 x 10/sup -3/ erg/cm/sup 2/ s. The observed electron fluxes show that a significant continuous electron precipitation occurs at the western edge of the South Atlantic magnetic anomaly even at times of low geomagnetic activity.

Authors:: Gaines, E E; Imhof, W L; Francis, W E; Walt, M; Rosenberg, T J

Publication Date:: Mon Dec 01 00:00:00 EST 1986

Research Org.:: Lockheed Palo Alto Research Laboratory, Palo Alto, California

OSTI Identifier:: 7021892

Resource Type:: Journal Article

Journal Name:: J. Geophys. Res.; (United States)

Additional Journal Information:: Journal Volume: 91:A12

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; EARTH ATMOSPHERE; ELECTRON PRECIPITATION; ANGULAR DISTRIBUTION; BALLOONS; BREMSSTRAHLUNG; DATA ANALYSIS; ELECTRON DENSITY; ENERGY SPECTRA; GEOMAGNETIC FIELD; LOSS CONE; SATELLITES; X-RAY SPECTRA; AIRSHIPS; CHARGED-PARTICLE PRECIPITATION; DISTRIBUTION; ELECTROMAGNETIC RADIATION; MAGNETIC FIELDS; RADIATIONS; SPECTRA; 640201* - Atmospheric Physics- Auroral, Ionospheric, & Magetospheric Phenomena

Citation Formats


                    Gaines, E E, Imhof, W L, Francis, W E, Walt, M, and Rosenberg, T J. Correlated electron and X ray measurements of quiet time electron precipitation: a comparative study of Bremsstrahlung production and transport in the atmosphere.  United States: N. p., 1986. 
        Web.  doi:10.1029/JA091iA12p13455.

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                    Gaines, E E, Imhof, W L, Francis, W E, Walt, M, & Rosenberg, T J. Correlated electron and X ray measurements of quiet time electron precipitation: a comparative study of Bremsstrahlung production and transport in the atmosphere.  United States.  https://doi.org/10.1029/JA091iA12p13455

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                    Gaines, E E, Imhof, W L, Francis, W E, Walt, M, and Rosenberg, T J. 1986.  
        "Correlated electron and X ray measurements of quiet time electron precipitation: a comparative study of Bremsstrahlung production and transport in the atmosphere".  United States.  https://doi.org/10.1029/JA091iA12p13455.

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@article{osti_7021892,

  title        = {Correlated electron and X ray measurements of quiet time electron precipitation: a comparative study of Bremsstrahlung production and transport in the atmosphere},

  author       = {Gaines, E E and Imhof, W L and Francis, W E and Walt, M and Rosenberg, T J},

  abstractNote = {Five cases of X ray observations from balloons coordinated with measurements of precipitating electrons were obtained during passes of the polar-orbiting satellite P78-1 near Siple, Antarctica (L--4.1), the launch point of the balloons. The observations, made during a geomagnetically quiet period in late December 1980 to early January 1981, showed small enhancements of the X ray fluxes (E>25 keV) and moderate trapped electron fluxes (E>68 keV) with pitch angle distributions extending into the edge of the loss cone sufficient to produce the approx. <0.5 dB of cosmic noise absorption recorded by the Siple 30-MHz riometer. Bremsstrahlung production and transport in the atmosphere were calculated using the measured electron fluxes, energy spectra, and pitch angle distributions for the source. The X ray fluxes and spectra calculated for the balloon altitudes were in good agreement with those measured from the balloons when the total energy deposition from electrons, E>10 keV, exceeded 2 x 10/sup -3/ erg/cm/sup 2/ s. The observed electron fluxes show that a significant continuous electron precipitation occurs at the western edge of the South Atlantic magnetic anomaly even at times of low geomagnetic activity.},

  doi          = {10.1029/JA091iA12p13455},

  url          = {https://www.osti.gov/biblio/7021892},
  journal      = {J. Geophys. Res.; (United States)},
number       = ,

  volume       = 91:A12,

  place        = {United States},

  year         = {Mon Dec 01 00:00:00 EST 1986},

  month        = {Mon Dec 01 00:00:00 EST 1986}

}

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