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
  • Other Sources  (5)
Collection
Source
Keywords
Years
  • 1
    facet.materialart.
    Unknown
    Abundance of interstellar aluminum (1984)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: New observations of Al II 1670 A, the only line of the dominant ionization stage of interstellar aluminum detected to date, are presented. Observations of ionized silicon are used to define an empirical curve of growth from which aluminum depletions can be derived. The depletion ranges from a factor of 10 in alpha Vir, with E(B-V) of about 0.04, to a factor of 1000 in omicron Per. The depletion is similar to that of iron, but a factor of 2-10 lower than that for silicon in the same stars. The observations of near-UV lines using the Copernicus V1 tubes with removal of a high cosmic-ray-induced fluorescent background are described.
    Keywords: ASTROPHYSICS
    Type: Astrophysical Journal, Part 1 (ISSN 0004-637X); 280; 600-607
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    New oscillator strengths for 18 resonance lines of N I and the interstellar abundance of nitrogen (1978)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Keywords: ASTROPHYSICS
    Type: Astrophysical Journal; vol. 224
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Further evidence for a color gradient in M15 (1992)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: Using data obtained at the Canada-France-Hawaii Telescope (CFHT) in subarcsecond seeing color maps are constructed in B - V and H-alpha - R of the central regions of the globular cluster M15. Comparison in B - V of the region within 0.31 pc of the cluster center with a coadded sample taken from the surrounding region demonstrates a color gradient, in the sense that the central region is bluer than the surrounding region at a high level of statistical significance. Analysis of the H-alpha - R color map indicates that the central region is 'H-alpha deficient', i.e., has a stronger H-alpha absorption line on average than the coadded region. This result argues against the possibility that the excess blue light from the central region is due to cataclysmic variables. Instead, two possible causes of the color gradient are (1) it may be due to a centrally concentrated population of faint blue stars, possibly resulting from binary-single star interactions, and (2) it may result from a central deficit of low-mass main-sequence stars.
    Keywords: ASTROPHYSICS
    Type: Astronomical Journal (ISSN 0004-6256); 103; 480-487
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    A color gradient in the globular cluster M15 (1989)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: A U-B color map of the central regions of the globular cluster M15 is constructed from data taken at the CFHT in subarcsec seeing. Analysis of the color distribution of the pixels in this map unambiguously demonstrates that the area within 6.6 arcsec of the center of the cluster is bluer than surrounding regions. The difference is apparently caused by a population of faint blue stars more prevalent in the core than elsewhere, and is consistent with post-core-collapse models which predict a centrally condensed distribution of cataclysmic variables.
    Keywords: ASTROPHYSICS
    Type: Astronomical Journal (ISSN 0004-6256); 98; 882-887
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    Discovery of a possible X-ray triple - 4U 1915-05 (1988)
    In:  Other Sources
    Details
    Publication Date: 2019-07-12
    Description: The optical counterpart of the 50 minute binary and X-ray burst source 4U 1915-05 has been identified with a 21st mag blue object. Extensive CCD photometric observations show that the optical modulation of the system defines a period of 50.4567 minutes with high precision and is thus probably the true orbital period, whereas the range of X-ray ray dip period values (49.7-50.1 minutes) reported previously are excluded. A model is described whereby the optical modulation is due to partial eclipse of the rim of the accretion disk by a low-mass companion star and the X-ray dips are due to absorption and scattering by blobs of material above and below the disk plane and with density proportional to the current mass transfer rate from the companion star. The 1 percent difference in periods may suggest that the system is a hierarchical triple with a third companion star of low-mass orbiting the binary ion in an about 2.5 day retrograde orbit. The possible origin of such a system by tidal capture in a globular cluster, since disrupted, is briefly discussed.
    Keywords: ASTROPHYSICS
    Type: Astrophysical Journal, Part 2 - Letters (ISSN 0004-637X); 334; L25-L29
    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...