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Anti-correlated hard X-ray time lag in GRS 1915+105: evidence for a truncated accretion disc

Manojendu Choudhury·A. R. Rao·Surajit Dasgupta·J. Pendharkar·K. Sriram·V. K. Agrawal
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Abstract

Multi-wavelength observations of Galactic black hole candidate sources indicate a close connection between the accretion disk emission and the jet emission. The recent discovery of an anti-correlated time lag between the soft and hard X-rays in Cygnus X-3 (Choudhury & Rao 2004) constrains the geometric picture of the disk-jet connection into a truncated accretion disk, the truncation radius being quite close to the black hole. Here we report the detection of similar anti-correlated time lag in the superluminal jet source GRS 1915+105. We show the existence of the pivoting in the X-ray spectrum during the delayed anti-correlation and we also find that the QPO parameters change along with the spectral pivoting. We explore theoretical models to understand this phenomenon.

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Manojendu Choudhury, A. R. Rao, Surajit Dasgupta, J. Pendharkar, K. Sriram, V. K. Agrawal. 2005-06-14. Anti-correlated hard X-ray time lag in GRS 1915+105: evidence for a truncated accretion disc. https://doi.org/10.1086/432675

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