G. Simnett

School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT, UK

The coronal imaging instruments on SOHO are able to study the response of the solar atmosphere to transient and impulsive energy releases. At the base of the corona, CDS can image active region and flare loops in selected spectral lines, and thus monitor the evolution of high temperature plasmas. EIT is able to study the onset of coronal mass ejections (CME) in the low corona. The LASCO coronagraphs are able to identify the fast (eg 1000 km/s) CMEs which may be responsible for accelerating some of the energetic charged particles which contribute to flares. Together these instruments should be complementary to HESSI in identifying the sites and nature of the energy deposition in flares, and identifying the particles responsible. Examples of the SOHO results in these areas will be presented. Also, recent LASCO observations have identified sites of reconnecting magnetic fields in the high corona, from which estimates of the magnetic field and particle density may be made. These new results will be presented and their relevance to the Fisk (JGR, 1996) magnetic field model will be discussed.