Keck Infrared Spectroscopy of Wz Sagittae: Detection of Molecular Emission from the Accretion Disk
نویسندگان
چکیده
Time-resolved IR spectroscopy of WZ Sge was obtained using NIRSPEC on Keck II. We detect CO and H2 emission from the accretion disk, placing WZ Sge in a rarefied class of astronomical objects including young stellar objects and high-luminosity early-type stars. During the eclipse phase, the molecular emission greatly weakens, but no firm evidence for the secondary star is seen, allowing new limits on its luminosity to be determined. The detection of molecular emission provides physical properties K and cm 3 within the 10 T p 3000 n 1 10 H outer disk. Such a cool, dense region not associated with areas of H i and He i emission provides the first observational confirmation of predictions made by accretion disk models. Subject headings: accretion, accretion disks — molecular processes — stars: dwarf novae — stars: individual (WZ Sagittae)
منابع مشابه
Keck IR Spectroscopy of WZ Sge: Detection of Molecular Emission from the Accretion Disk
Time-resolved IR spectroscopy of WZ Sge was obtained using NIRSPEC on Keck II. We detect CO and H2 emission from the accretion disk placing WZ Sge into a rarefied class of astronomical objects including YSOs and high luminosity early-type stars. During the eclipse phase, the molecular emission greatly weakens but no firm evidence for the secondary star is seen allowing new limits on its luminos...
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