Continuously driven OFC: A simple model of solar flare statistics

Abstract

We investigate a finite driving rate version of the Olami-Feder-Christensen (OFC) model with particular attention to the correlations between events and the statistics of waiting times. We also discuss the emergence of characteristic frequencies as well as a broad band background in the power spectrum of its activity. The system, which is usually not in a Self Organised Critical (SOC) state, can be described as being on the edge of SOC. Its critical features depend on the system bulk dissipation and driving rates, and in this sense the concept of "universality" must be used with care. Interestingly, the driven model shows many similarities and correspondences with observations from the physics of stellar flares suggesting they may be considered a manifestation of general behaviours of complex system dynamics.