天体物理中自组织临界现象的观测和模拟
摘要
<p indent="0mm">Self-organized criticality (SOC) is a critical state of a nonlinear dynamical system or a complex system that is continuously driven toward a critical value of instability threshold independent of external parameters, resulting in scale-free, fractal-diffusive, and intermittent avalanches or energy releases with power-law distributions. Since its introduction in 1987, the concept of SOC has been widely used to explain the power-law frequency distributions of nonlinear dynamical systems. We review the observations and simulations of SOC phenomena in astrophysics, identify the roles of SOC and MHD turbulence in producing astrophysical instabilities, and discuss potential applications of SOC in space weather as well as some critical challenges that must be addressed in the future.