The launch of coronal mass ejections: White light and x ray observations in the low corona
Abstract
As part of an ongoing program to determine the processes which lead to the launch of solar coronal mass ejections (CMEs) we present a thorough examination of periods where there are observations from the hard X ray imaging spectrometer on the Solar Maximum Mission which are complementary to observations made by the MkIII K-coronameter on Hawaii. At the time of the observations no attempt was made to produce compatible data sets so the analysis is hampered by unfortunate timing and pointing. Nevertheless, with the analysis of six events we are able to draw some useful conclusions which agree with the findings of our previous work but dispute the scenarios presented by most theoretical models of the CME launch and the CME/flare relationship. To summarize briefly our results: (1) None of the CME launches occur in coincidence with a flare onset, (2) flares which do occur in the vicinity of a CME launch site occur both after the CME onset and in one foot of the CME structure, (3) there is weak X ray activity also associated with the footpoints of the CME structures and these indicate the presence of large coronal structures which underlie the CME structures, (4) there are X ray enhancements after all of the CME onsets; in some cases these are bright enough to be classed as flares, and in others they are lesser brightenings which we refer to as subflares.
- Publication:
-
Journal of Geophysical Research
- Pub Date:
- March 1989
- DOI:
- 10.1029/JA094iA03p02333
- Bibcode:
- 1989JGR....94.2333H
- Keywords:
-
- Optical Measurement;
- Solar Corona;
- Stellar Mass Ejection;
- X Ray Astronomy;
- Coronal Loops;
- Solar Flares;
- Solar Maximum Mission;
- Solar X-Rays;
- Spectrometers;
- Solar Physics;
- Astrophysics;
- and Astronomy: Flares;
- and Astronomy: Corona;
- and Astronomy: Magnetic fields;
- and Astronomy: X rays;
- gamma rays;
- and neutrinos