DYNAMICAL PROPERTIES OF STELLAR CORONAS AND STELLAR WINDS. I. INTEGRATION OF THE MOMENTUM EQUATION
The hydrodynamic momentum and mass flow equations are integrated for a stellar corona with spherical symmetry about the center of the star. The coronal temperature is taken to be a known function T(r) of radial distance. The general properties of the equations are discussed, and it is shown that if the corona is tightly bound by the solar gravitational field, so that the thermal velocity is small compared to the gravitational escape velocity, and if the coronal temperature declines outward more slowly than 1/r, then the corona is quasi- static at its base and expands to supersonic velocity in space. No alternative is available. The stellar mass loss resulting from the expansion is determined by the coronal temperature between the base of the corona and the point at which the flow becomes supersonic. The amount by which the velocity of the resulting stellar wind exceeds the thermal velocity in the corona depends principally upon the temperature beyond the point where the flow becomes supersonic. (auth)
- Research Organization:
- Univ. of Chicago
- NSA Number:
- NSA-18-010739
- OSTI ID:
- 4101952
- Journal Information:
- Astrophysical Journal (U.S.), Journal Name: Astrophysical Journal (U.S.) Vol. Vol: 139; ISSN ASJOA
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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