Energy release, flares, and particle acceleration in the region between the components of a close binary system

The physical conditions prevailing in between the components of a close binary system are discussed. The plasma there can become heated, leading to flares and acceleration of particles. Tails should develop in the magnetospheres of the member stars, and bow shocks should form. Substorms could result, with acceleration processes occurring at the shock fronts. Possible systems of this kind include dwarf novae (U Gem and Z Cam stars) and certain dMe flare stars. Close binary systems could in fact make a substantial or even a predominant contribution to the field of galactic cosmic rays, especially those of low and medium energy.