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
    Abundance determination in solar active region (1994)
    In:  Other Sources
    Details
    Publication Date: 2011-08-24
    Description: An improved method has been developed to evaluate element abundances from emission line intensities of thin plasmas, depending on the differential emission measure (DEM) of the source. Observations made by the Solar EUV Rocket Telescope and Spectrograph (SERTS) Rocket EUV Spectrograph are used to perform a detailed analysis of the DEM distribution for temperatures larger than 10(exp 5) K in a solar active region. Comparison of the DEM distributions obtained by means of lines from different elements allows the verification of relative abundances for the most common elements of the solar corona, and gives an abundance estimates for the minor components, such as Na, Al, Ar, Cr, Mn and Zn.
    Keywords: SOLAR PHYSICS
    Type: Advances in Space Research (ISSN 0273-1177); 14; 4; p. (4)163-(4)166
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    Polarization results of solar X-rays from OSO-7 (1974)
    In:  Other Sources
    Details
    Publication Date: 2011-08-16
    Description: Polarization measurements of solar X-ray events that were obtained with an instrument on OSO-7 are presented. The results appear to be consistent with the results of Tindo et al. on the existence and magnitudes of polarization. A comparison with polarization predictions when X-rays are produced by radial beams of electrons gives two examples of deviations from such a model.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 37; Aug. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Limb-brightening observations from the OSO-7 satellite. I - Electron density and temperature of the non-equatorial corona from EUV lines of Fe XIV and other Fe ions (1974)
    In:  Other Sources
    Details
    Publication Date: 2011-08-16
    Keywords: SOLAR PHYSICS
    Type: Astronomy and Astrophysics; 37; 2, De; Dec. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    The solar physics Shuttle/Spacelab program and its relationship to studies of the flare build-up (1976)
    In:  Other Sources
    Details
    Publication Date: 2011-08-17
    Description: The main phase of solar physics (including flare-buildup) research on Shuttle/Spacelab during the 1980s centers around the use of facility instruments for multiple-user, multiple flight operations. Three main facilities are being considered: a meter-class optical telescope for visible and near-UV wavelengths, an EUV/XUV/soft X-ray facility, and a hard X-ray imaging facility (including a full-sun 5-600 keV spectrometer, a nuclear gamma ray spectrometer, and an X-ray polarimeter for the 5-100 keV range). Smaller instruments designed for specific observations and other classes of instruments such as solar monitors that are not on the facility level are also being considered.
    Keywords: SOLAR PHYSICS
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    Coronal temperatures and temperature gradients from OSO-7 spectroheliograms (1976)
    In:  Other Sources
    Details
    Publication Date: 2011-08-17
    Description: Temperatures and temperature gradients for the outer corona are obtained from brightness gradients of EUV lines that were measured with the spectroheliograph on OSO-7. Brightness gradients show considerable deviations from isothermal model calculations that include collisional excitation and photoexcitation. A negative temperature gradient that gives both positive and negative ion-abundance gradients appears to be able to account for the discrepancy. For the 284-A of Fe XV, perhaps the strongest line from the outer corona, measurements during 1972 appear to be consistent with a temperature near 2.3 million K near the equator at about 1.3 solar radii from the solar center and with temperature-gradient values near -0.7 that extend from as low as 1.2 to about 1.8 solar radii. Temperatures from strong lines of Fe XIV and Fe XVI indicate that variations of about 200,000 K exist along lines of sight where emission is appreciable. There appears to be some agreement between these results and temperature measurements from ion abundances in the solar wind and the Doppler width of the 5303-A line.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 47; Apr. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unknown
    Limb-brightening observations from the OSO-7 satellite. II - Comparison of Abel-inverted intensities of Fe XIV and Fe XIII EUV emission lines with predictions (1976)
    In:  Other Sources
    Details
    Publication Date: 2011-08-17
    Description: Intensities of Fe XIV and Fe XIII EUV emission lines obtained at coronal locations beyond the limb by the Goddard spectroheliograph on the OSO 7 satellite have been corrected for the wavelength dependence of the instrument's sensitivity and have been Abel-inverted to provide a valid comparison with theoretical predictions for each ion. Details of the Abel-inversion procedure are given, including explicit formulas for application of Bracewell's (1956) method. The intensity ratios of pairs of lines originating from a common level are compared with expected theoretical transition probability ratios over a range of heliocentric distance; deviations in some cases yield information about adjacent unclassified lines. Comparison of the observations with predictions for Fe XIV and Fe XIII shows generally good agreement, with a few interesting discrepancies that may imply a corresponding need for more accurate collisional excitation cross sections. The same comparison yields the variation of electron density with heliocentric radius for each ion separately; the two density functions are found to agree within a factor of three.
    Keywords: SOLAR PHYSICS
    Type: Astronomy and Astrophysics; 53; 2, De; Dec. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unknown
    Slowly varying component of extreme ultraviolet solar radiation and its relation to solar radio radiation (1974)
    In:  Other Sources
    Details
    Publication Date: 2011-08-16
    Description: A study of the correlations between solar EUV line fluxes and solar radio fluxes has been carried out. A calibration for the Goddard Space Flight Center EUV spectrum is suggested. The results are used to obtain an equation for the absolute EUV flux for several lines in the 150- to 400-A region and the total flux of 81 intense lines in the region, the 2800-MHz radio flux being used as independent variable.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 79; Oct. 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 8
    facet.materialart.
    Unknown
    On coronal Fe abundances and temperatures from XUV emission lines (1977)
    In:  Other Sources
    Details
    Publication Date: 2011-08-17
    Description: Data obtained by the OSO-7 spectroheliograph on strong XUV lines of five different Fe ions from the outer equatorial corona are presented. Interpretation of the data with a spherically symmetric model atmosphere gives average ion abundances for lines of sight at 0.3 solar radii from the limb. Fe XVI is usually more abundant than Fe XV, XIV, XII and IX, but there are times when Fe XII is more abundant than the other ions. The deviation of measured relative abundances of Fe XII, XIV, and XVI from predictions of ionization equilibrium at one temperature seems to indicate that there are appreciable temperature variations along lines of sight. Element abundances are very uncertain since they appear to depend so heavily on likely but unknown density irregularities along lines of sight.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 53; Aug. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 9
    facet.materialart.
    Unknown
    Energy balance in a magnetically confined coronal structure observed by OSO-7 (1975)
    In:  Other Sources
    Details
    Publication Date: 2011-08-16
    Description: A model of a coronal region of enhanced Fe XV and Fe XVI emission is developed and its energy balance is examined using extreme ultraviolet observations from OSO-7 together with calculations of possible force-free coronal magnetic field configurations. The coronal emissions overlying the photospheric boundary between regions of opposite magnetic polarity are found to be associated with generally nonpotential (current-carrying) magnetic fields in the forms of arches with footpoints in regions of opposite polarity. The orientation of these arches relative to the neutral line changes with degree of ionization of the emitting ion (which we infer from our limb observations to be a function of height) and may be evidence of differing electric currents along various field lines. The appearance of a coronal arch, seen side-on, can conveniently be represented by a parabola and a detailed analysis shows this to be a realistic approximation that should be generally useful in analyzing two-dimensional pictures of coronal structures.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 43; Aug. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 10
    facet.materialart.
    Unknown
    Observation of possible Fe XVII 2p5 3p/1S0/ - 2p5 3s/1P1, 3P1/ transitions in spectra of a solar active region and flare (1975)
    In:  Other Sources
    Details
    Publication Date: 2011-08-16
    Description: Expected wavelengths and relative intensities are obtained from previous calculations for the hitherto unobserved transitions 2p5 3p(1SO) - 2p5 3s(1P1, 3P1) in Fe XVII. A candidate pair of lines at 197.05 A and 242.09 A was found in laboratory spectra and appears to be present in the spectra of a solar active region observed by the OSO-7 Goddard spectroheliograph as well as in the spectrum of a Skylab-observed solar flare.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 43; July 197
    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...