TURBULENT CORONAL HEATING AND THE DISTRIBUTION OF NANOFLARES

We perform direct numerical simulations of an externally driven two-di mensional magnetohydrodynamic system over extended periods of time to simulate the dynamics of a transverse section of a solar coronal loop. A stationary and large-scale magnetic forcing was imposed, to model t he photospheric motions at the magnetic loop footpoints. A turbulent s tationary regime is reached, which corresponds to energy dissipation r ates consistent with the heating requirements of coronal loops. The te mporal behavior of quantities such as the energy dissipation rate show s clear indications of intermittency, which are exclusively due to the strong nonlinearity of the system. We tentatively associate these imp ulsive events of magnetic energy dissipation (from 5 x 10(24) to 10(26 ) ergs) to the so-called nanoflares. A statistical analysis of these e vents yields a power-law distribution as a function of their energies with a negative slope of 1.5, which is consistent with those obtained for flare energy distributions reported from X-ray observations.