On the potential role of concentrated field-aligned currents in solarphysics.
Abstract
The consequences of the existence of intense field-aligned currents on energy storage and dissipation in the solar atmosphere are investigated. Joule heating may be the reason for the chromospheric network as seen in H alpha and for plages in active regions. A wide range of Ohmic dissipation rates can exist without altering the local chromospheric temperature by more than a factor of two. Generation of narrow current tubes by turbulent motions in and below the photosphere could provide the energy to the corona released during flares. The primary energy release during these events could proceed by untwisting of the flux tubes. The high and strongly inhomogeneous pressure distribution set up in the corona as a result of reconnection in multiple narrow current sheets can act as generator of even more intense currents (up to 1000 a/sqm A/m2). They generate the low temperature flare by classical Joule heating of the chromosphere and particle beams greater than 100 MeV by linear acceleration in localized field-aligned potential drops, which may be preferentially set up below the transition region.
- Publication:
-
Small Scale Plasma Processes in the Solar Chromosphere/Corona, Interplanetary Medium and Planetary Magnetospheres
- Pub Date:
- August 1987
- Bibcode:
- 1987ESASP.275..205H
- Keywords:
-
- Current Sheets;
- Electric Energy Storage;
- Field Aligned Currents;
- Line Current;
- Ohmic Dissipation;
- Particle Acceleration;
- Solar Physics;
- Faculae;
- Resistance Heating;
- Solar Atmosphere;
- Solar Corona;
- Solar Flares;
- Solar Temperature;
- Solar Physics;
- Solar Atmosphere:Energy Transfer