Investigation of the energy release in flare kernels Original Research Article

We have investigated the heating rate, EH, in flare kernels for a number of M-class flares. We have found that: 1) The heating rate decreases with the altitude of kernel. We explain this as a result of magnetic field decrease with the height in the corona, i.e. the decrease of the available magnetic energy H2/8π, per unit volume. 2) However, the temperature of the investigated kernels does not decrease with the altitude. We explain this as being the result of decreasing conductive losses from the kernel with increasing height, which compensates the decrease of EH. We have divided the investigated flares into three groups: low, intermediate and higher loops, and calculated the median values of the heating rate, EH, and of other parameters for each group. The low loops (compact flares) have high heating rates EH.