Supersonic turbulent convection, inhomogeneities of chemical composition, and the solar neutrino problem.
Abstract
A new theory is proposed for the evolution of the sun that can account for the present low flux of solar neutrinos. It is argued that resistive segregation of interstellar grain material during early stages of stellar formation may lead to an initial chemically inhomogeneous sun having a small metal-rich convective core surrounded by a corresponding metal-deficient homogeneous radiatively stable envelope. Extension of conventional mixing-length theory of convection to the regime of large mixing lengths permits development of a large supersonic turbulent stress in the interior of the convective core. This additional stress raises the gas kinetic temperature at the center of the star but lowers it at the core edge. The result is a star at solar age consisting of a small burnt-out core surrounded by a barely consumed hydrogen-rich envelope and having a neutrino flux of order 1.2-1.8 SNU. The predicted sharp transition in luminosity at the time when the central turbulent core burns out may be related to the mysterious and sudden onset of the Cambrian Period some 570 million years ago.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- July 1976
- Bibcode:
- 1976A&A....50...59P
- Keywords:
-
- Neutrinos;
- Solar Flux;
- Solar Physics;
- Stellar Evolution;
- Convective Flow;
- Metallic Stars;
- Solar Corpuscular Radiation;
- Stellar Envelopes;
- Turbulent Flow;
- Solar Physics