Dynamical Properties of Stellar Coronas and Stellar Winds. I. Integration of the Momentum Equation.

Abstract

view Abstract Citations (121) References (17) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Dynamical Properties of Stellar Coronas and Stellar Winds. I. Integration of the Momentum Equation. Parker, E. N. Abstract The hydrodvnamic 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 elodty 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. Publication: The Astrophysical Journal Pub Date: January 1964 DOI: 10.1086/147740 Bibcode: 1964ApJ...139...72P full text sources ADS | Related Materials (4) Part 2: 1964ApJ...139...93P Part 3: 1964ApJ...139..690P Part 4: 1965ApJ...141.1463P Part 5: 1966ApJ...143...32P