Magnetic flux transport and the sunspot-cycle evolution of coronal holes and their wind streams

Abstract

view Abstract Citations (100) References (39) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Magnetic Flux Transport and the Sunspot-Cycle Evolution of Coronal Holes and Their Wind Streams Wang, Y. -M. ; Sheeley, N. R., Jr. Abstract The relationships between magnetic flux transport from active regions and the formation and evolution of coronal holes are examined through numerical simulations. The model utilized is based on the assumption that coronal holes represent open field regions, and that the solar-wind speed at 1 AU is universely correlated with the divergence rate of the coronal field. The evolution of coronal holes and wind streams during 1980 - 1990 is discussed, along with flux transport and the evolution of open field regions, and focus is placed on declining, rising, and maximum phases. It is concluded that supergranular diffusion spreads active region flux over the solar surface and wipes out pockets of mixed polarity, thus creating unipolar areas containing open field lines; differential rotation spreads flux in longitude and it combines with diffusion to create axisymmetric polar holes from the original active-region fields; and meridional flow accelerates the decay of low-latitude holes by carrying flux to midlatitudes. Publication: The Astrophysical Journal Pub Date: December 1990 DOI: 10.1086/169492 Bibcode: 1990ApJ...365..372W Keywords: Coronal Holes; Magnetic Flux; Solar Activity Effects; Solar Wind; Sunspot Cycle; Transport Properties; Magnetohydrodynamics; Solar Corona; Solar Magnetic Field; Solar Physics; HYDROMAGNETICS; SUN: ACTIVITY; SUN: CORONA; SUN: MAGNETIC FIELDS; SUN: SOLAR WIND full text sources ADS |