Coupling between QPOs and broadband noise components in GRS 1915+105

Understand

We explore the use of the bispectrum for understanding quasiperiodic oscillations.

• The bispectrum is a statistic which probes the relations between the relative phases of the Fourier spectrum at different frequencies.
• The use of the bispectrum allows us to break the degeneracies between different models for time series which produce identical power spectra.
• We look at data from several observations of GRS 1915+105 when the source shows strong quasi-periodic oscillations and strong broadband noise components in its power spectrum.