Fast variability as a probe of the smallest regions around accreting black holes

  title={Fast variability as a probe of the smallest regions around accreting black holes},
  author={Magnus Axelsson and L. Hjalmarsdotter and C Done},
  journal={Monthly Notices of the Royal Astronomical Society},
We extract the spectra of the fastest variability (above 10 Hz) from the black hole XTE J1550-564 during a transition from hard to soft state on the rise to outburst. We confirm previous results that the rapid variability contains no significant disc component despite this being strongly present in the total spectrum of the softer observations. We model ionized reflection significantly better than previous work, and show that this is also suppressed in the rapid variability spectrum compared to… 

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