2003/12/18 by Aya Kubota, Chris Done, Kubota, Aya +1
Engineering · Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics (astro-ph) #FOS: Physical sciences #Mechanics and Biomechanics Studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0312493
12 pages, 10 figures, and 3 tables, accepted for publication for MNRAS
openalex publication_date 2003/12/18 · arxiv created 2004/06/18 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The 1998 outburst of the bright Galactic black hole binary system XTE J1550-564 was used to constrain the accretion disc structure in the strongly Comptonised very high state spectra. These data show that the disc emission is not easily compatible with the constant area L ~ T4 behaviour seen during the thermal dominated high/soft state and weakly comptonised very high state. Even after correcting for the effects of the scattering geometry, the disc temperature is always much lower than expected for its derived luminosity in the very high state. The simplest interpretation is that this indicates that the optically thick disc is truncated in the strongly Comptonised very high state, so trivially giving the observed continuity of properties between the low/hard and very high states of Galactic black holes.