Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-02-28
AIP Conf.Proc.599:310,2001
Astronomy and Astrophysics
Astrophysics
16 pages; invited talk at the meeting "X-ray Astronomy 1999: Stellar Endpoints, AGN and the Diffuse Background", held in Bolog
Scientific paper
10.1063/1.1434644
Accreting black holes and neutron stars in their hard (low) state show not only very similar X/gamma-ray spectra but also that the behaviour of their light curves is quite similar which can be quantified as having similar power-density spectra and Fourier-frequency-dependent time/phase lags. Taken together this argues for a common mechanism of the X/gamma-ray production in these objects. This mechanism is probably a property of the accretion flow only since it does not depend on the nature of the compact object. In this paper, I review the observational data paying most attention to the properties of the temporal variability such as the time/phase lags that hopefully can help us to discriminate between different theoretical models. I also discuss the models developed to account for the basic observational facts. Particularly, I show that the commonly used Compton cloud models with constant temperature cannot explain variable sources without violating the energy conservation law. Alternative models where time lags are related to the spectral evolution during X-ray flares are discussed and compared with observations. Compton reflection from the outer edge of the accretion disc is shown to markedly affect the time lag Fourier spectrum.
No associations
LandOfFree
Time Lags in Compact Objects: Constraints on the Emission Models does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Time Lags in Compact Objects: Constraints on the Emission Models, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Time Lags in Compact Objects: Constraints on the Emission Models will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-198786