ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1995-1999
  • 1975-1979  (3)
  • 1979  (3)
Collection
Keywords
Publisher
Years
  • 1995-1999
  • 1975-1979  (3)
Year
  • 1
    facet.materialart.
    Unknown
    Impulsive, quasi-periodic variations in ionospheric absorption of cosmic radio noise. (1979)
    Society of Geomagnetism and Earth, Planetary and Space Sciences
    Details
    Publication Date: 1979-01-01
    Description: Cosmic radio noise data, acquired with a fast-response 30 MHz riometer at Siple Station, Antarctica (L≈4), show evidence of weak impulsive quasi-periodic variations in ionospheric absorption. Significant amplitude variations approaching 0.02 dB, approximately the statistical noise limit of the measurement, have been measured. An event typically will consist of 3 to 5 cycles of oscillation (∽60 to 90 sec period) and can occur during locally disturbed or quiet geomagnetic conditions. Usually the oscillations are not related closely to magnetic field fluctuations as measured on the ground at Siple or in the conjugate area. Conjugate bremsstrahlung X-ray data, available for one event, suggest that these absorption variations are caused by the impact on the ionosphere of a modulated flux of energetic electrons from the magnetosphere. Limited statistics on the location of the plasmapause suggest that these events occur close to, but on either side of, the boundary of the plasmasphere. These absorption oscillations may be another manifestation of the process that produces short-term intensity and phase variations in fixed-frequency sub-ionospheric LF and VLF wave propagation. Further studies of this unique modulated precipitation/absorption phenomenon and its relationship to hydromagnetic wave disturbances in the magnetosphere will be conducted with a set of riometer and magnetometer stations appropriately sited in a latitude array. © 1979, Society of Geomagnetism and Earth, Planetary and Space Sciences. All rights reserved.
    Print ISSN: 0022-1392
    Topics: Geosciences
    Published by Society of Geomagnetism and Earth, Planetary and Space Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Direct energy inputs to the middle atmosphere (1979)
    In:  CASI
    Details
    Publication Date: 2006-01-12
    Description: As a working definition of the extent of the middle atmosphere (MA), the height range from 30 to 100 km was adopted. The neutral and ionic composition and the dynamics within this height range are, for the most part, poorly understood. From available information, the importance of various particle and photon energy sources, including their variability, for ionization of the neutral atmosphere in this height range is assessed. The following topics are discussed: (1) penetration of the MA by particle and electromagnetic energy; (2) ionization sources for the MA; (3) galactic cosmic rays; (4) solar H Ly alpha, other EUV, and X-rays; (5) magnetospheric electrons and bremsstrahlung X-rays; and (6) solar cosmic rays.
    Keywords: GEOPHYSICS
    Type: NASA. Goddard Space Flight Center Middle Atmosphere Electrodyn.; p 43-70
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Pc 3 magnetic pulsations and precipitation of energetic electrons (1979)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Description: The synchronous altitude satellite ATS 1 data and near-conjugate measurements of bremsstrahlung X-rays and ground magnetic variations were used to analyze an event of modulated auroral zone electron precipitation and magnetic pulsations in the Pc range. Transverse, azimuthal, nearly linearly polarized waves observed at ATS 1, ground magnetic pulsations at College, Alaska, and intervals of modulated electron precipitation centered on local magnetic moon, and noted in the X-ray data from Fort Yukon, Alaska, are discussed, noting that the origin of the Pc 3 waves is attributed to local field line resonances induced by Kelvin-Helmholtz instability at the magnetopause. The wave resonance model can explain observed differences in the pulsation activity at the ground, balloon, and satellite if account is taken of the spatial sensitivities of the techniques and the location of observing sites with respect to the probable location of resonant field lines. The data suggest that electron precipitation pulsations will correlate with Pc 3 magnetic pulsations when substorm injections coupled with azimuthal drift provide enhanced energetic particle fluxes with dayside resonance regions.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research; 84; Aug. 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...