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
  • ASTROPHYSICS  (14)
  • GEOPHYSICS  (3)
  • Cell & Developmental Biology  (1)
  • Nerves, degeneration  (1)
  • 1985-1989  (19)
  • 1960-1964
  • 1945-1949
Collection
Keywords
Publisher
Years
Year
  • 11
    facet.materialart.
    Unknown
    Star formation and nuclear activity in Seyfert galaxies (1988)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: A probable correlation between radio structure and IRAS spectrum in Seyfert galaxies is reported. For Seyfert galaxies known to exhibit the observational characteristics of vigorous star formation, the correlation between 1.4 GHz and 60 micron fluxes is in excellent agreement with that found for other extragalactic star formation regions. The far-IR radiation observed by IRAS from these galaxies is predominantly thermal emission from dust heated by hot stars. On the other hand, Seyfert galaxies with radio emission dominated by 'linear' structures tend to have relatively flat 25-100 micron spectra, and the ratio of their 1.4 GHz to 60 micron flux densities is considerably higher than that for star-forming regions. The radio and far-IR emission from this class appear to be dominated by the Seyfert nucleus, with the far-IR originating directly from a nonthermal source or from dust heated by one.
    Keywords: ASTROPHYSICS
    Type: Astronomy and Astrophysics (ISSN 0004-6361); 206; 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 12
    facet.materialart.
    Unknown
    Kinematics and ionization of extended gas in active galaxies. IV - The Seyfert 2 galaxy NGC 4388 (1988)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: The results of direct CCD imaging and long-slit medium-dispersion spectroscopy of the extended narrow-line-emitting gas in the nearby Seyfert 2 galaxy NGC 4388 are presented. The spectra are used to investigate the distribution, kinematics, and ionization structure of the excited gas in the regions surrounding the nucleus out to a distance of about 4.8 kpc. The data support earlier suggestions that the galaxy, which appears to lie near the core of the Virgo cluster, has been tidally distorted, possibly by the nearby cluster core galaxies M84 or IC 3303. Much of the highly ionized gas in the galaxy appears to be distributed in two wide cones originating from the nucleus and extending above and below the disk. Explanations are offered for the distribution of this gas and for the remainder of the gas above and below the disk.
    Keywords: ASTROPHYSICS
    Type: Astrophysical Journal, Part 1 (ISSN 0004-637X); 334; 584-596
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 13
    facet.materialart.
    Unknown
    0714 - 2914 (M4-1) - Another Seyfert galaxy with aligned radio continuum and optical emission-line morphologies (1989)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: Direct imaging and long-slit spectroscopic mapping of the emission-line gas in the Seyfert 2 galaxy 0714 - 2914 (M4-1, MCG - 5-18-2) are reported. The nuclear regions contain an extended (1 kpc size), high-excitation nebulosity that is well aligned with the jet-like nonthermal radio source. The profiles of Forbidden O III 5007A are asymmetric, with extended red wings to the north and west of the nucleus and extended blue wings to the south and east. This switch in the sense of asymmetry is accounted for in terms of a combination of normal rotational motions in the galaxy disk and high-velocity outflow or infall associated with the Seyfert activity.
    Keywords: ASTROPHYSICS
    Type: Astronomical Journal (ISSN 0004-6256); 98; 2056-206
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 14
    facet.materialart.
    Unknown
    A Sm-Nd and Pb isotope study of Archaean greenstone belts in the southern Kaapvaal Craton, South Africa (1989)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: An Sm-Nd and Pb study on a wide variety of lithologies in Archaean greenstone belt fragments in the southern Kaapvaal Craton reveals a complex petrogenetic history. The fragments are important because they represent a 350 km transect through the craton south of Barberton to its southern margin. The Commondale greenstone belt yields a precise Sm-Nd age of 3334 + or - 18 Ma on an exceptionally well preserved peridotite suite of komatiitic affinity. The wide range of Sm/Nd from 0.6 to 1.0 is attributed to the unusual occurrence of orthopyroxene in the spinifex-bearing rocks. A considerably younger age of about 3.2 Ga is suggested for the Nondweni greenstone belt close to the southern margin of the craton on the basis of separate Sm-Nd isochrons on individual lithologies ranging from komatiite, through komatiitic basalt and basalt to felsic volcanic rocks. On the basis of the present study the greenstone belts appear to have been emplaced at progressively younger ages toward the southern margin of the craton.
    Keywords: GEOPHYSICS
    Type: Earth and Planetary Science Letters (ISSN 0012-821X); 96; 2-Jan; 89-105
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 15
    facet.materialart.
    Unknown
    The radio source in the very luminous gamma-ray Seyfert galaxy MCG 8-11-11 (1986)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: VLA high resolution observations of the Seyfert 1.5 galaxy MCG 8-11-11 at 2 and 6 cm show the center of the galaxy to contain a triple radio source of 400 pc, with a less than 30-pc diameter central component that may be identified as the center of the galaxy. The triple source is in turn embedded in more diffuse emission which has a major axis position angle similar to that in the optical galaxy, but differing from the position angle of the triple source by 50 deg. While the overall morphology of the source is S-shaped, the curvature of the triple source at the ends is abrupt rather than continuous and gradual. It appears that the core radio emission in Seyfert 1 and 1.5 galaxies may be weakly correlated with their X-ray emission.
    Keywords: ASTROPHYSICS
    Type: Royal Astronomical Society, Monthly Notices (ISSN 0035-8711); 218; 711-719
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 16
    facet.materialart.
    Unknown
    Radio structure in the inner 1 arcsecond of NGC 1068 (1987)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: High-resolution VLA and VLBI observations of NGC 1068 at several different wavelengths are reported. These observations provide new information about the triple radio source in the central arcsec (75 pc) of the galaxy. The 21-cm European VLBI Network observations at 0.05-arcsec resolution detect a core of flux density 89 + or - 10 mJy. This core is dominated by a component less than 20 marcsec (1.5 pc) in diameter that has a brightness temperature of about 10 to the 8th K. Two more components may have been detected by the VLBI observations, one on either side of the compact core. At 0.07-arcsec resolution, the 1.3-cm VLA map of the central arcsec of NGC 1068 reveals a C-shaped radio morphology on scales from 10 to 50 pc. A comparison of the relative locations of the three components in the VLA and VLBI maps shows that the compact core in the VLBI map probably should be identified with the central component in the 1.3- and 2-cm VLA maps. If this identification is correct, the central component in the VLA maps is the actual nucleus of the galaxy. The core of the inner triple radio source may contain a significant flat-spectrum component. The presence of a compact core and the evidence for bending strengthen the argument that the inner triple radio source is produced by a mechanism similar to that operating in powerful radio galaxies. For a minimum-energy configuration, magnetic-field strengths of about 1 mG and energy densities of about 100 nerg/cu cm are found for the components of this source.
    Keywords: ASTROPHYSICS
    Type: Astronomical Journal (ISSN 0004-6256); 93; 22-28
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 17
    facet.materialart.
    Unknown
    Radio observations of a hard X-ray selected sample of active galaxies (1987)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: Radio observations of a hard X-ray selected sample of active galaxies obtained with the VLA and Parkes radio telescopes are discussed, and the ratio of the radio to X-ray flux density is used to determine the degree of radio-loudness of the galaxies. A continuous distribution of the degree of radio loudness is found amongst the sample galaxies, and no evidence for distinct radio-quiet and radio-loud populations is noted. The X-ray and radio luminosity is shown to be nonlinearly correlated, with the radio-loud objects all having high X-ray luminosity.
    Keywords: ASTROPHYSICS
    Type: Royal Astronomical Society, Monthly Notices (ISSN 0035-8711); 228; 521-531
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 18
    facet.materialart.
    Unknown
    Studies of isolated neutron stars, pulsars and pulsar-driven nebulae with the advanced X-ray astrophysics facility (AXAF) (1987)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: The AXAF will signal a revolution in the understanding of neutron stars, pulsars, and Crab Nebula-type supernova remnants. The mission will provide vital and detailed observational data relevant to the physics of superdense matter inside neutron stars, to the acceleration and radiation of nonthermal particles in their magnetospheres, and to the processes whereby these relativistic particles and magnetic fields fuel the surrounding synchrotron nebulosities on scales of parsecs. Highlights of the results should include (1) detection of thermal surface emission from neutron stars, (2) greatly enlarged samples of pulsars that emit magnetospheric (nonthermal) X-rays, and (3) high resolution (spatial and spectral) maps of the nebulae powered by slowing pulsars. The AXAF will extend these studies to external galaxies, being capable of detection of young pulsars and remnants in normal galaxies like M31, in starburst systems like M82, and probably even in galaxies as distant as the Virgo cluster.
    Keywords: ASTROPHYSICS
    Type: Astrophysical Letters and Communications (ISSN 0888-6512); 26; 1-2
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 19
    facet.materialart.
    Unknown
    X-ray observations of supernova remnants resembling the Crab Nebula (1986)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: Out of the three SNRs G291.0 - 0.1, G308.7 + 0.0, and G328.4 + 0.2, which resemble the Crab Nebula in many of their radio properties, the present Einstein Observatory search was able to detect only the first, which is noted to have very extended X-ray emission with strong central brightening. Given the large distances and hydrogen column densities of the other two SNRs, their X-ray limits are consistent with membership in the Crab Nebula-like group. The evolutions of radio luminosity, X-ray luminosity, and the ratio of the two luminosities with remnant diameter are reassessed for this SNR class. No evidence is found for a radio luminosity decrease with diameter (age).
    Keywords: ASTROPHYSICS
    Type: Astrophysical Journal, Part 1 (ISSN 0004-637X); 302; 718-726
    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...