Rotational evolution of solar-type stars. I - Main-sequence evolution

Journal Article · Mon Jul 01 00:00:00 EDT 1991 · Astrophysical Journal; (United States)

DOI:https://doi.org/10.1086/170269· OSTI ID:5157339

Macgregor, K B; Brenner, M ^[1]

---

1. High Altitude Observatory, Boulder, CO (United States)

A simple, parameterized model for the redistribution of angular momentum within the interiors of solar-type stars is presented. By incorporating it with a description of angular momentum loss through the action of a magnetically coupled wind, tracing the rotational histories of low-mass dwarf stars for a variety of initial conditions and parameter specifications is accomplished. The results of calculations are discussed for the rotational evolution of a 1 solar mass star, from the time of its arrival on the zero-age main sequence to the age of the present-day sun. Best agreement is with observational constraints for (1) a surface magnetic field strength which is largely independent of surface angular velocity omega for rapid rotation, and approximately linearly dependent on omega for approximately solar values, and (2), a time scale for angular momentum transfer from the core to the convection zone which remains essentially constant throughout the evolution, with magnitude of a about 10 million yr. This value is approximately equal to the initial wind braking time. These results are discussed in the context of a qualitative description of angluar momentum redistribution by magnetic fields in the radiative interiors of solar-type stars. 48 refs.

• OSTI ID: 5157339
• Journal Information: Astrophysical Journal; (United States), Vol. 376; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
MAIN SEQUENCE STARS
STAR EVOLUTION
STAR MODELS
ANGULAR MOMENTUM
ANGULAR VELOCITY
DWARF STARS
MAGNETIC FIELDS
MAGNETIC STARS
MOMENTUM TRANSFER
ROTATION
STELLAR WINDS
MATHEMATICAL MODELS
MOTION
STARS
STELLAR ACTIVITY
VELOCITY
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
Radio & X-Ray Sources