RHESSI / SOHO / TRACE:

Working Group on Particle acceleration and Transport

 

The main goal of this group is to form an integrated picture of particle acceleration and transport in the context of solar flares.  Such a picture should both be consistent with current observations and theory and yet not be unduly distorted by the limitations of current observational or theoretical tools. 

 

QUESTIONS:

 

Some representative questions might include some that were posed in the recent ACE/RHESSI/WIND meeting in Taos and others that represent fresh perspectives:

 

  1. What is the link between particle acceleration and reconnection?
  2. What is the role of magnetic topology and complexity on particle acceleration and transport?
  3. What is the respective role of shocks and stochastic acceleration, with emphasis on their interrelation to the energy release process(es).
  4. To what extent does the limitations of current observations determine our picture of the processes involved.  Such observational limitations would include not only size scale issues (both on sub-resolution and very large size scales) but also energy regimes to which observational access is difficult (non-thermal electrons at low energies in the presence of thermal plasma and ions below ~5 MeV).  Although the properties of these particles are virtually unobserved, they may still play a major role in the energetics and the energy release.

 

 

ORGANIZATIONAL STRATEGY:

 

The specific topics will depend on the interests and activities of members of the group.  Based on discussions prior to the workshop, we will try to identify common areas of interest,  key calculations and/or observations so as to identify specific topics that might be considered most effectively at the workshop itself.  Attendees will be encouraged to present the results of their pre-workshop activities as posters and to bring visual materials with which to illustrate the discussions. 

 

Building on individual contributions, the discussions themselves will try to place the specific contributions into a broader perspective, hopefully overcoming the tendency to treat  these phenomena  as disjoint topics.  For example, magnetic energy release mechanism(s), particle acceleration and particle transport are usually discussed as separate issues. ÒHeatingÓ and acceleration also tend to be addressed as separate issues, although we are aware that they are strongly coupled.  Finally the magnetic topology hosting flares is often considered separately from  the acceleration and transport of high energy particles.  The simple magnetic topologies and the lack of information from the sub-resolution or very large scale physical processes may lead us to simplistic models for the flare(s) which are not wholly self-consistent.  Our goal is to develop a more integrated picture of magnetic energy release, heating and particle acceleration in solar flares.