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Outbursts in Symbiotic BinariesTwo models have been proposed for the outbursts of symbiotic stars. In the thermonuclear model, outbursts begin when the hydrogen burning shell of a hot white dwarf reaches a critical mass. After a rapid increase in the luminosity and effective temperature, the white dwarf evolves at constant luminosity to lower effective temperatures, remains at optical maximum for several years, and then returns to quiescence along a white dwarf cooling curve. In disk instability models, the brightness rises when the accretion rate from the disk onto the central white dwarf abruptly increases by factors of 5-20. After a few month to several year period at maximum, both the luminosity and the effective temperature of the disk decline as the system returns to quiescence. If most symbiotic stars undergo thermonuclear eruptions, then symbiotics are probably poor candidates for type I supernovae. However, they can then provide approx. 10% of the material which stars recycle back into the interstellar medium. If disk instabilities are the dominant eruption mechanism, symbiotics are promising type Ia candidates but recycle less material into the interstellar medium.
Document ID
Document Type
Contractor or Grantee Report
Sonneborn, George (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Kenyon, Scott J. (Smithsonian Astrophysical Observatory Cambridge, MA, United States)
Date Acquired
August 21, 2013
Publication Date
February 1, 2004
Subject Category
Funding Number(s)
Distribution Limits
Work of the US Gov. Public Use Permitted.
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