Fluxes of energy, momentum, and mass from the Sun in various types of solar-wind flow: Prognoz-7 observations.
Abstract
The authors have previously used Prognoz-7 measurements of hydrodynamic parameters to identify five types of solar wind. They investigate the variations in a number of MHD parameters (including fluxes of energy momentum, and mass) in different types of flows. In the heliospheric current sheet (HCS), and in plasma which is created by coronal mass ejections, they find that the ratio of ion thermal pressure to magnetic pressure is more often larger than average. Momentum fluxes are identical in quasi-stationary flows (i.e., in flows from regions where the magnetic field configuration is that of a streamer of a coronal hole). There is an increase in the momentum flux in flows which are perturbed by time-dependent phenomena in the solar corona, and in the HCS. In perturbed flows, and in the HCS, the flux of thermal and kinetic energy in the ions is 2 - 3 times larger than in quasi-stationary flows. Despite this result, when taking into account the frequency with which the various types of flows occur, and their durations, the Sun expends 2 - 5 times more thermal and kinetic energy in solar-wind flows from regions where the coronal magnetic field diverges superradially than it expends in the HCS or in perturbed flows. And these expenditures are 1.5 - 2 times larger than those which occur in flows from regions where the magnetic field divergence is small.
- Publication:
-
Cosmic Research
- Pub Date:
- May 1993
- Bibcode:
- 1993CosRe..30..672E