Location of the electron acceleration region in solar flares

✍ Scribed by S. R. Kane; R. P. Lin

• Publisher: Springer
• Year: 1972
• Tongue: English
• Weight: 520 KB
• Volume: 23
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00148108

✦ Synopsis

Observations of impulsive solar flare X-rays > 10 keV by the OGO-5 sa.telIite and the measurements of energetic solar electrons made with the Explorer-35 and Explorer-41 (IMP-5) satellites during the period March 1968-September 1969 have been analyzed in order to determine the ion density in the X-ray source region as well as the location of the electron acceleration region in the solar atmosphere. If we assume that the cfiqciency of escape of the accelerated electrons into interplanetary space is ~ 10 -~, the observations arc found to be consistent with the following interprctation: (i) the ion density in the X-ray source region varies from event to event and lies between I0 *~ and 10 lj ions cm ~ for those events in which the impulsive X-ray emission could be detected; (ii) for those events in which no impulsive emission was detected above threshold, the ion density in the X-ray source was ..:~ 10 ,~ ions cm-~; (iii) at least in some small solar flares the region where the electrons are accelerated during the flash phase is located in the lower corona.