The photon-index-time-lag correlation in black hole X-ray binaries

DOI: 
10.1093/mnras/stx2683
Publication date: 
01/02/2018
Main author: 
Reig, Pablo
IAA authors: 
Costado, María Teresa
Authors: 
Reig, Pablo;Kylafis, Nikolaos D.;Papadakis, Iossif E.;Costado, María Teresa
Journal: 
Monthly Notices of the Royal Astronomical Society
Refereed: 
Yes
Publication type: 
Article
Volume: 
473
Pages: 
4644-4652
Abstract: 
We have performed a timing and spectral analysis of a set of black hole binaries to study the correlation between the photon index and the time lag of the hard photons with respect to the soft ones. We provide further evidence that the timing and spectral properties in black hole X-ray binaries are coupled. In particular, we find that the average time lag increases as the X-ray emission becomes softer. Although a correlation between the hardness of the X-ray spectrum and the time (or phase) lag has been reported in the past for a handful of systems, our study confirms that this correlated behaviour is a global property of black hole X-ray binaries. We also demonstrate that the photon-index-time-lag correlation can be explained as a result of inverse Comptonization in a jet.
Database: 
ADS
SCOPUS
URL: 
https://ui.adsabs.harvard.edu/#abs/2018MNRAS.473.4644R/abstract
ADS Bibcode: 
2018MNRAS.473.4644R
Keywords: 
stars: black holes;galaxies: jets;X-rays: binaries;Astrophysics - High Energy Astrophysical Phenomena