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Hard X-ray lags in GRO J1719-24

F. van der Hooft·C. Kouveliotou·J. van Paradijs·W. S. Paciesas·W. H. G. Lewin·M. van der Klis·D. J. Crary·M. H. Finger·B. A. Harmon·S. N. Zhang
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Abstract

We have used the Fourier cross spectra of GRO J1719-24, as obtained with BATSE, to estimate the phase lags between the X-ray flux variations in the 20--50 and 50--100 keV energy bands as a function of Fourier frequency in the interval 0.002--0.488 Hz. Our analysis covers the entire ~80 day X-ray outburst of this black-hole candidate, following the first X-ray detection on 1993 September 25. The X-ray variations in the 50--100 keV band lag those in the 20--50 keV energy band by an approximately constant phase difference of 0.072 +/- 0.010 rad in the frequency interval 0.02--0.20 Hz. The peak phase lags in the interval 0.02--0.20 Hz are about twice those of Cyg X-1 and GRO J0422+32.These results are consistent with models for Comptonization regions composed of extended non-uniform clouds around the central source.

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F. van der Hooft, C. Kouveliotou, J. van Paradijs, W. S. Paciesas, W. H. G. Lewin, M. van der Klis, D. J. Crary, M. H. Finger, B. A. Harmon, S. N. Zhang. 1999-01-13. Hard X-ray lags in GRO J1719-24. https://doi.org/10.1086/307346

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