Research on the Stochastic Nonlinear Self-excited Oscillation Model of the Disk-corona System in Black Hole Accretion

Based on hydrodynamic theory, a stochastic nonlinear self-excited oscillation model of the corona covering an accretion disk was constructed using the Rayleigh ordinary differential equation. This model simulates the observed light variability of low-mass X-ray binaries by oscillatory energy variations and successfully fits the low-frequency quasi-periodic oscillations (LFQPOs) in the power density spectrum of GRS 1915+105. The study shows that the power spectral density profile of the coronal oscillation luminosity resembles observational results, producing single or double-peaked generalized energy stochastic resonances that closely match LFQPOs and their harmonics. The frequency of stochastic resonance is approximately twice the natural frequency of radial oscillation of the corona, matching the observed fundamental LFQPO frequency. The results suggest that the origin of LFQPOs in X-ray radiation may stem from the modulation of radiation luminosity by stochastic self-excited coronal oscillations induced through disk-corona interactions.