May 14, 2000

Sample QPO from XTE J1550-564

Sample time series and Fourier spectrum of QPOs from XTE J1550-564



Above: (left) This 40 second snippet of data captured by the Rossi X-ray Timing Explorer shows how the x-ray flux from XTE J1550 oscillates during a flare in 1998. Numbers on the vertical axis represent the number of x-ray photons per second in the 2 to ~30 keV energy band. (right) The Fourier power spectrum of the same 40s time series shows a dominant spike at 0.3 Hz, corresponding to a period of about 3 1/3 seconds. Although 0.3 Hz is dominant, the spectrum reveals frequency components extending to 1 Hz and higher.