Institute of Astronomy
Radio Astronomy and Plasma Physics Group
Eidgenössische Technische Hochschule Zürich
Swiss Federal Institute of Technology,  Zürich
          
Interpretation of Coherent Emission
Problems:
1.  Role in flare phase and geometry unclear
(Pulsations: preflare, flare, postflare?)
2. Many theories possible because of unknown plasma parameters
(high or low beta?)
3. No confirmations by observations!
Coherent emissions are produced by plasma waves,
which are usually caused by non-thermal electrons or ions
(beams, currents, shocks, magnetic traps).