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
  • 1
    facet.materialart.
    Unknown
    Measurement of macroscopic plasma parameters with a radio experiment: Interpretation of the quasi-thermal noise spectrum observed in the solar wind (1983)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The ISEE-3 SBH radio receiver has provided the first systematic observations of the quasi-thermal (plasma waves) noise in the solar wind plasma. The theoretical interpretation of that noise involves the particle distribution function so that electric noise measurements with long antennas provide a fast and independent method of measuring plasma parameters: densities and temperatures of a two component (core and halo) electron distribution function have been obtained in that way. The polarization of that noise is frequency dependent and sensitive to the drift velocity of the electron population. Below the plasma frequency, there is evidence of a weak noise spectrum with spectral index -1 which is not yet accounted for by the theory. The theoretical treatment of the noise associated with the low energy (thermal) proton population shows that the moving electrical antenna radiates in the surrounding plasma by Carenkov emission which becomes predominant at the low frequencies, below about 0.1 F sub P.
    Keywords: SOLAR PHYSICS
    Type: JPL Solar Wind Five; p 377-383
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    A survey on initial results of the Helios plasma experiment (1977)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Description: The reported results are mainly based on data obtained during the first part of the Helios-1 mission. The sun was very quiet during the considered period. The data are, therefore, representative for comparatively stationary conditions in the solar corona. Data obtained concerning the protons were evaluated by means of a special computer routine. The significance of the data is discussed, taking into account the status of the corona and the interplanetary plasma during the considered part of the Helios-1 mission, fast stream structures in the region between 0.3 and 1 AU, radial gradients of fast and slow solar wind, and the separation of proton double streams and alpha-particles. Attention is also given to the 'strahl' in the electron distribution, differences between fast streams and slow plasma on the basis of the observed electron distributions, and radial gradients in the case of solar wind electron parameters.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysics - Zeitschrift fuer Geophysik; 42; 6, 19; 1977
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Electron-rich particle events and the production of gamma-rays by solar flares (1984)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: The abundance of electrons of 5-50 MeV energies relative to protons of similar energy has been determined in a total of 49 particle events of apparently solar origin during the year 1980. Most events with high electron abundances appear to have been produced by flares which also produced observable fluxes of gamma-rays. The overall distribution of abundances is consistent with that measured in 1968-1970 at similar energies, but is systematically lower in electron content than abundance distributions measured at lower energies. Electron-rich particle events have harder electron spectra than more normal events, and are never accompanied by strong interplanetary shocks. Therefore, an investigation is conducted to decide whether observations are consistent with models in which energetic particles are accelerated by a shock produced at the flare site. It is concluded that, in such models, the variable nature of the interplanetary particle events must reflect some fundamental but variable property of the shocks - possibly their direction of propagation. An outward moving shock may produce a particle event in interplanetary space whereas a shock directed toward the sun may produce a flux of particles in the lower solar atmosphere which generate the gamma-radiation.
    Keywords: SOLAR PHYSICS
    Type: Astrophysical Journal, Part 1 (ISSN 0004-637X); 283; 439-449
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    Protons from the decay of solar flare neutrons (1983)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: Fluxes of energetic protons in interplanetary space are observed which are interpreted as the decay products of neutrons generated in a solar flare on 1982 June 3 at 11:42 UT. Because of the particular geometry of this event the spectrum of neutrons escaping from the sun can be constructed with great accuracy in the kinetic energy range 10-100 MeV. The resulting spectrum places stringent constraints on the free parameters used in previously published calculations of neutron production in solar flares. An estimate is made of the diffusion mean free path of charged particles in the interplanetary medium in a new way.
    Keywords: SOLAR PHYSICS
    Type: Astrophysical Journal, Part 1 (ISSN 0004-637X); 274; 875-882
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    The relation of type II radio bursts to solar energetic particles observed at earth (1981)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: Observations of particle events associated with type II radio bursts as recorded on the ISEE-3 spacecraft are reported. Data on burst events following flares of Sept. 23,1978 and Aug. 18, 1979 yield time histories of the particle fluxes, which exceeded 25 MeV energy. The profiles of the Category-1 type II bursts display a continuous release of particles, which was concluded by no decrease in the fluxes until after the passage of the shock. The continuous nature of the recorded events suggests that the secondary acceleration process associated with the type II bursts is maintained as the flare shock propagates through interplanetary space, and may be the source of the energetic particles which propagate with the shock.
    Keywords: SOLAR PHYSICS
    Type: International Cosmic Ray Conference; Jul 13, 1981 - Jul 25, 1981; Paris; France
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unknown
    Unusual properties of particle events associated with solar flare gamma ray events (1981)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: An attempt to establish a link between gamma rays observed at the earth with solar flare areas highly enriched with electrons is presented. Two hour averages of the counting rates of 5-100 MeV electrons and 25-145 MeV protons performed on the ISEE-3 spacecraft were correlated with solar flares with a maximum intensity of 6-11 MeV electrons and 25-44 MeV protons recorded by other observers. The coverage was part of the Solar Maximum Mission, which attained a 50 percent coverage. Gamma ray associated events showed high ratios of electrons to protons, about 0.2, and electrons with energies greater than 80 MeV were observed, which are values high enough to produce the highest gamma rays observed, 40 MeV. The available data for electron, proton, and rare isotope fluxes and the time histories of the fluxes are noted to provide a data base for further information on solar flares and particle acceleration mechanisms.
    Keywords: SOLAR PHYSICS
    Type: International Cosmic Ray Conference; Jul 13, 1981 - Jul 25, 1981; Paris; France
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unknown
    Solar flare neutron fluxes derived from interplanetary charged particle measurements (1983)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The first observation of interplanetary protons produced by the decay of solar neutrons made by Evenson et al. (1983) after a solar flare which occurred on June 3, 1982, is expanded, extending the measurement of the spectrum of the decay protons to higher energy. The spectrum of the decay protons for the June 21, 1980, neutron event observed by Chupp et al. (1982) is also determined. The measurements suggest that neutron emission from solar flares is isotropic and that different flares emit neutrons with similar spectra. The importance of such measurements in the study of interplanetary propagation of charged particles is discussed.
    Keywords: SOLAR PHYSICS
    Type: International Cosmic Ray Conference; Aug 22, 1983 - Sep 03, 1983; Bangalore; India
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 8
    facet.materialart.
    Unknown
    Observations of the wavelength dependence of the average contrast of sunspots (1981)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The Extreme Limb Photometer has been used to observe the contrast of sunspots and faculae in conjunction with the Active Cavity Radiometer Irradiance Monitor on the SMM spacecraft. Some of these observations were obtained at five wavelengths from 0.43 to 1.01 micron. The largest average contrast at 0.52 micron was -17% over an area 38.5 x 51 in covering only the largest spot in Boulder AR no. 2684. It was found, for five sunspots, far from the limb, that the wavelength dependence of the contrast, averaged over the entire sunspot, followed a 1/lambda-law. No evidence was found for localized bright emission around the sunspots with an upper limit of about 3%, a limit set by the granular intensity rms variation of 1.3% at 0.52 micron.
    Keywords: SOLAR PHYSICS
    Type: The physics of sunspots; Conference; Jul 14, 1981 - Jul 17, 1981; Sunspot, NM
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 9
    facet.materialart.
    Unknown
    Sudden disappearance of anisotropies in the September 23, 1978 solar flare (1980)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: Shortly after the onset of the particle event associated with the September 23, 1978 solar flare the University of Chicago instrument on the ISEE-3 spacecraft was measuring large anisotropies in the flux of protons with energies between 32 and 150 MeV. Several hours after the onset, the anisotropy nearly disappeared on a timescale of minutes. We present the time history of the anisotropy in this event and discuss it in terms of available information on the solar and interplanetary conditions at that time.
    Keywords: SOLAR PHYSICS
    Type: International Cosmic Ray Conference; Aug 06, 1979 - Aug 18, 1979; Kyoto; Japan
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 10
    facet.materialart.
    Unknown
    Modulation of low energy electrons and protons near solar maximum (1975)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The intensities of cosmic-ray electrons in the energy range from 24 to 235 MeV and of protons in the ranges 40 to 150 MeV and greater than 700 MeV are compared with the neutron intensity data over the period 1968 to 1972. Correlation plots between these various components show a marked break following the June 9, 1969 Forbush decrease. The resulting hysteresis curve is best explained as a sudden change in the rigidity dependence of solar modulation. A variation in the size of the solar cavity is also possible but not likely.
    Keywords: SOLAR PHYSICS
    Type: International Cosmic Ray Conference; Aug 15, 1975 - Aug 29, 1975; Munich
    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...