Włodzimierz Kluźniak40 min

Millisecond X-ray variability (QPOs): a signature of strong gravity?

Many accreting X-ray sources in low-mass binaries (LMXBs) exhibit rapid variability (first observed with the Rossi X-ray Timing Explorer in 1996). This millisecond variability exhibits reproducible regularities, and yet its origins remain controversial. Evidence connecting the high frequency QPO phenomenon to strong-field effects of gravity will be reviewed. However, other effects may conspire to mimic signatures of general relativity.