ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    Publication Date: 2011-08-16
    Description: The radio spectral data of OH471 and OQ172 are shown in a graph along with decompositions of the spectra into canonical self-absorbed synchrotron components. The minimum number of canonical components consistent with the data is used. Theoretically expected angular radii and time scales are presented in a table. The estimation of the angular size of a compact radio source with known spectral form rests upon the establishment of its maximum brightness temperature.
    Keywords: SPACE SCIENCES
    Type: Nature; 250; Aug. 9
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2019-06-27
    Description: A photographic 200-inch plate of the compact cluster of galaxies Shakhbazian I is presented and discussed. The size of the cluster, the nature of the galaxies and the very small velocity dispersion all make this cluster unique. The mass-to-light ratio of the cluster is 0.3-0.5.
    Keywords: SPACE SCIENCES
    Type: Astronomical Society of the Pacific; vol. 85
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2019-06-27
    Description: Both thermal and nonthermal models for the radiation from QSOs and Seyfert galaxies are discussed in terms of the size limitations imposed by the models. It is concluded that if daily fluctuations in the luminosity of Seyfert galaxies are confirmed and do represent a maximum size for the sources, then neither dust models nor ordinary synchrotron models can explain the radiation. Colgate's proposal involving the production of infrared radiation by a nonthermal plasma is considered, and a more detailed theory is derived which indicates that the process cannot produce infrared radiation.
    Keywords: SPACE SCIENCES
    Type: Astrophysical Journal; 172; Mar. 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2019-06-27
    Keywords: SPACE SCIENCES
    Type: Astrophysical Journal; 186; Dec. 15
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2019-06-27
    Description: Photographic far UV solar spectra during eclipse of 7 March 1970, discussing coronal lines, prominences and quiet atmosphere structure
    Keywords: SPACE SCIENCES
    Type: ; - PHYSICAL AND RADIO
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2019-06-27
    Description: A set of restrictions upon the magnetic field and visible angular size of a canonical nonthermal source (one whose emission is incoherent electron synchrotron) has been obtained in another paper. The degree of electron anisotropy and magnetic field disordering were left as free parameters. In the present paper these restrictions are applied to the variable compact radio sources 3C 84, 3C 120, 3C 273, 3C 279, 3C 454.3, CTA 102, 3C 446, PKS 2134 + 004, VRO 42.22.01, and OJ 287. The theoretically derived angular sizes for these sources are in reasonable agreement with published VLBI sizes, provided that the characteristic pitch angles are not extremely small. The magnetic field strengths determined from the degree of circular polarization are generally compatible with field strengths derived from the self-absorption and synchrotron self-Compton conditions, again provided that the pitch angles are not too small. It is argued that the self-absorption optical depth cannot be much less than unity near the low-frequency turnovers; otherwise, serious discrepancies with observation result.
    Keywords: SPACE SCIENCES
    Type: Astrophysical Journal; 192; Sept. 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2019-06-27
    Keywords: SPACE SCIENCES
    Type: Astrophysical Journal; 191; July 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2019-06-27
    Description: Combined photometric and radiometric observations can be used to determine the albedos and radii of airless solar-system objects such as asteroids and most satellites. We use recent observations of the Galilean satellites to derive a new calibration of this method and use these results to calculate the radii and albedos of eight bright asteroids. Possible errors in the method are also discussed.
    Keywords: SPACE SCIENCES
    Type: Astronomical Journal; 79; Aug. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2019-06-27
    Description: It is shown from the equation of radiative transfer that the visual attenuation of an optically thick, spherically symmetric circumstellar cloud of dust can be small compared to that produced by an equal optical depth of interstellar dust. The reasons for this are the moderately large albedos of the grains and their tendency to emphasize forward scattering.
    Keywords: SPACE SCIENCES
    Type: Astronomical Society of the Pacific; vol. 85
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2019-06-27
    Description: Some recent observations of the galactic center appear at first sight to have made the character of the radio source Sgr A unclear. The flatness of the usually quoted spectrum, the lack of any measured polarization, the presence of hydrogen recombination lines, and the radio-infrared luminosity ratio are all consistent with Sgr A being a rather hot H II region. It is shown here, however, that when flux measurements between 80 MHz and 91000 MHz are all included and the multiple nature of the source is accounted for, the spectral index exceeds 0.4 - much too steep to be bremsstrahlung. There is, therefore, no question that Sgr A is a nonthermal source. It is further argued on the basis of a comparison of appearance, energetics and the recent results which no longer put Sgr A exactly at the center of the galaxy that Sgr A could be a supernova remnant rather than a miniature of active extragalactic radio sources.
    Keywords: SPACE SCIENCES
    Type: Astronomy and Astrophysics; 30; 1, Ja; Jan. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...