The extension of solar magnetic fields into interplanetary space [electronic resource].
- Washington, D.C. : United States. Dept. of Energy, 1991.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
- Physical Description:
- Pages: (13 pages) : digital, PDF file
- Additional Creators:
- Los Alamos National Laboratory, United States. Department of Energy, and United States. Department of Energy. Office of Scientific and Technical Information
- Restrictions on Access:
- Free-to-read Unrestricted online access
- The flow of coronal plasma into interplanetary space results in outward transport of the solar magnetic field. The prevailing open'' interplanetary magnetic field is rooted in the corona and wraps up into a spiral due to the rotation of the Sun. This simple configuration, however, is disrupted by magnetically distinct coronal mass ejections (CMEs) which erupt from the solar corona into interplanetary space. Observations of CMEs at 1 AU reveal electron signatures indicating a closed magnetic topology, postulated to be: (1) magnetic bottles,'' tied to the corona at both ends; (2) plasmoids that are completely disconnected from the Sun; or (3) flux ropes which have topologies intermediate between (1) and (2). With either the magnetic-bottle or flux rope hypothesis, the inward and outward flux at 1 AU should increase indefinitely as CMEs continue to erupt. Using a new techniques to calculate the 2-D flux through 1 AU from single spacecraft measurements, we show that while there is a solar cycle variation to the magnetic flux, it clearly does not grow without bound. This suggests that either CMEs are closed plasmoids which add to no new flux to the interplanetary medium, or that the opening of new flux by CMEs is balanced via reconnection elsewhere in the corona. We suggest that the this latter process may be dominant and describe observation from the Solar Maximum Mission coronagraph which are consistent with reconnection above helmet streamers in the corona. Such disconnections would serve to return closed field arches to the Sun and release open. U-shaped structures into the solar wind. Coronal disconnections appear in some cases to be triggered by pressure pulses caused by CME eruption elsewhere, suggesting a dynamic flux-balance process. We describe a class of solar wind structures, called heat flux dropouts, in which the solar wind electron heat flux, driven by magnetic connection to the hot corona, is absent or greatly reduced.
- Report Numbers:
- E 1.99:la-ur-91-2781
E 1.99: conf-9109254--1
- Other Subject(s):
- Published through SciTech Connect.
Solar connection with transient interplanetary processes (SOLTIP), Castle Liblice (Czechoslovakia), 30 Sep - 5 Oct 1991.
Phillips, J.L.; McComas, D.J.
- Funding Information:
View MARC record | catkey: 13827248