Astrophysics (Index)About

quasi-periodic oscillation

(type of flicker of some X-ray sources)

The term quasi-periodic oscillation (QPO) is used in X-ray astronomy for a type of variability in X-ray sources that is interpreted as variability in the accretion of a compact object from its accretion disk. The variation is random, but can show a peak frequency (e.g., in the 50-1000 Hz range), which can vary over time. Analysis can reveal information regarding the host and its accretion, an example being estimates of a central black hole's mass.

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