Study of the thermal size-energy release relationship in solar flares with RHESSI

Mikko Väänänen

S. Pohjolainen, J. Huovelin, O. Vilhu

A number of compact central (within 425 arcseconds from solar centre) flares are imaged with RHESSI and their spatial sizes of 1/e from maximum emission are measured. The measured spatial sizes are correlated with their spectroscopically derived thermal energy release, and physical and mathematical relationships between these two variables are discussed in light of the current models of flare physics. The observations from compact flares are also compared with different flare morphologies and flares in limb areas of the sun.