Similar behaviors between FRB 121102 and solar type III radio bursts

Fast radio bursts (FRBs) are bright milliseconds radio transients with large dispersion measures (DMs), and can be used as potential astrophysical and cosmological tools. Many models for FRB progenitors have been proposed. However, none of them can explain all the observational properties, meaning that FRBs remain one of the most intriguing mysteries in astronomy. The statistical properties of radio bursts can unveil the underlying physics. Here, we report statistical results of the repeating FRB 121102, and show that FRB 121102 and solar type III radio bursts share four statistical properties: power-law frequency distributions for energies, fluxes, durations and waiting times. All of the distributions can be explained by avalanche models of self-organized criticality (SOC) systems. It is well known that solar type III radio burst arises from the nonlinear conversion of Langmuir waves generated by two-stream instability of electron beams, which are accelerated by bursty magnetic reconnections. The similarities support that repeating FRBs are coherent emissions from magnetic-reconnection-driven beams in the magnetospheres of magnetars.