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Accession Number N20120010319
Title Nature of QPO Phase Lags in Black Hole Candidates.
Publication Date May 2012
Media Count 5p
Personal Author N. Shaposhnikov
Abstract Observations of quasi-periodic oscillations (QPOs) in X-ray binaries hold a key to understanding many aspects of these enigmatic systems. Complex appearance of the Fourier phase lags related to QPOs is one of the most puzzling observational effects in accreting black holes. In this Letter we show that QPO properties, including phase lags, can be explained in a framework of a simple scenario, where the oscillating media provides a feedback on the emerging spectrum. We demonstrate that the QPO waveform is presented by the product of a perturbation and a time delayed response factors, where the response is energy dependent. The essential property of this effect is its non-linear and multiplicative nature. Our multiplicative reverberation model successfully describes the QPO components in energy dependent power spectra as well as the appearance of the phase lags between signal in different energy bands. We apply our model to QPOs observed by Rossi X-ray Timing Explorer in BH candidate XTE J1550-564. We briefly discuss the implications of the observed energy dependence of the QPO reverberation times and amplitudes to the nature of the power law spectral component and its variability.
Keywords Black holes(Astronomy)
Delay
Energy spectra
Feedback
Perturbation
Power spectra
Variability
Waveforms
X ray binaries
X ray timing explorer

 
Source Agency National Aeronautics and Space Administration
NTIS Subject Category 54C - Astrophysics
99A - Analytical Chemistry
Corporate Author Goddard Space Flight Center, Greenbelt, MD.
Document Type Journal article
Title Note N/A
NTIS Issue Number 1226
Contract Number N/A

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