Investigating state transition luminosities of BH X-ray binaries in the outburst decay
Abstract
We have performed a comprehensive spectral and timing analyses of black hole(BH) X-ray transients during outburst decay in order to obtain the distribution ofstate transition luminosities. Using the archival data of the Rossi X-ray Timing Ex-plorer (RXTE), we have calculated the state transition luminosities for 12 BH sourcesin 19 different outbursts and for disk and power-law luminosities separately. Our re-sults show a tight clustering in bolometric power-law luminosity around 1.85 ± 0.43% Eddington (EDD) during transition to the hard state as well as disk black bodyluminosity around 4.92 ± 2.19 % EDD during a transition to hard-intermediate state.We also report a third clustering during index transition for power-law with a valueand error of 2.85 ± 0.81 % EDD. We discuss the reasons for clustering and possible ex-planations for sources that show a transition luminosity below or above the generaltrend.
- Publication:
-
42nd COSPAR Scientific Assembly
- Pub Date:
- July 2018
- Bibcode:
- 2018cosp...42E3481V