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
  • SPACE SCIENCES  (3)
  • Astronomy  (1)
  • 1
    facet.materialart.
    Unknown
    Near-infrared Variability in the 2MASS Calibration Fields: A Search for Planetary Transit Candidates (2008)
    In:  Other Sources
    Details
    Publication Date: 2018-06-11
    Description: The Two Micron All Sky Survey (2MASS) photometric calibration observations cover approximately 6 square degrees on the sky in 35 'calibration fields,' each sampled in nominal photometric conditions between 562 and 3692 times during the 4 years of the 2MASS mission. We compile a catalog of variables from the calibration observations to search for M dwarfs transited by extrasolar planets. We present our methods for measuring periodic and nonperiodic flux variability. From 7554 sources with apparent K(sub s) magnitudes between 5.6 and 16.1, we identify 247 variables, including extragalactic variables and 23 periodic variables. We have discovered three M dwarf eclipsing systems, including two candidates for transiting extrasolar planets.
    Keywords: Astronomy
    Type: The Astrophysical Journal Supplement Series; Volume 175; 191-228
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    Formation and destruction rates of interstellar H2 (1974)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Description: In the model of Hollenbach et al. (1971), hydrogen molecules are formed on grains. Molecular hydrogen is destroyed by absorption of radiation in the Lyman bands. A study has been conducted regarding the formation and destruction rates of molecular hydrogen. The ultraviolet radiation field has been calculated to determine the rate of molecular hydrogen destruction resulting from absorption in the Lyman bands. An estimate of an upper limit for the molecular hydrogen formation rate is obtained from observations involving stars in which very little molecular hydrogen is observed.
    Keywords: SPACE SCIENCES
    Type: Astrophysical Journal; 191; July 15
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Chlorine-bearing molecules in interstellar clouds (1974)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Description: The reaction Cl(+) + H2 yielding HCl(+) + H is rapid, and it leads to the formation of the molecules HCl(+), H2Cl(+), and HCl. It may be possible to detect HCl(+) near 3600 A, and HCl may be observable at 1291 A. Also, photodissociation of HCl(+) may be a significant source of protons within clouds, and chemical heating resulting from the destruction of chlorine-bearing molecules may account for perhaps 1-10 per cent of the expected cooling from diffuse interstellar clouds.-
    Keywords: SPACE SCIENCES
    Type: Astrophysical Journal; 190; May 15
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    Helium abundance at the galactic center (1974)
    In:  Other Sources
    Details
    Publication Date: 2019-06-27
    Description: We suggest that the low abundance of ionized helium in H II regions at the galactic center can be explained by selective absorption of helium-ionizing photons by dust within the ionized gas. This model requires an extrapolation to 500 A of the rapid increase of the extinction measured between 1500 A and 1000 A with the Copernicus satellite, and it assumes that the dust absorbs most of the Lyman continuum.
    Keywords: SPACE SCIENCES
    Type: Astrophysical Journal; 188; Mar. 15
    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...