Abstract
The influence of collisional energy losses on stochastic particle acceleration in impulsive solar flares is considered in the context of preferential acceleration of heavy ions. It is shown that ion pre-acceleration in a reconnecting current sheet mitigates the effect of collisional energy losses, thus removing a strong sensitivity of the resulting anomalous abundances on the initial ion charge states. As an example, the expected Fe/O enhancement factors are computed and shown to be comparable with those observed with ACE SEPICA in a series of impulsive flares in 1998. One consequence of the model is that the preferential acceleration of heavy ions can occur only when the plasma gas pressure is large enough, β≈me/mp, which may explain the observed correlation between the heavy ion enrichment and selective 3He acceleration in impulsive flares.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
