Accretion disc evolution in GRO J1655-40 and LMC X-3 with relativistic and non-relativistic disc models

0575397 - ASÚ 2024 RIV US eng J - Článek v odborném periodiku
Yilmaz, Anastasiya - Svoboda, Jiří - Grinberg, V. - Boorman, Peter G. - Bursa, Michal - Dovčiak, Michal
Accretion disc evolution in GRO J1655-40 and LMC X-3 with relativistic and non-relativistic disc models.
Monthly Notices of the Royal Astronomical Society. Roč. 525, č. 1 (2023), s. 1288-1310. ISSN 0035-8711. E-ISSN 1365-2966
Grant CEP: GA ČR(CZ) GX21-06825X
Institucionální podpora: RVO:67985815
Klíčová slova: accretion * accretion discs * relativistic processes
Obor OECD: Astronomy (including astrophysics,space science)
Impakt faktor: 4.8, rok: 2022
Způsob publikování: Omezený přístup
https://doi.org/10.1093/mnras/stad2339

Black hole X-ray binaries are ideal environments to study the accretion phenomena in strong gravitational potentials. These systems undergo dramatic accretion state transitions and analysis of the X-ray spectra is used to probe the properties of the accretion disc and its evolution. In this work, we present a systematic investigation of & SIM, 1800 spectra obtained by Rossi X-Ray Timing Explorer Proportional Counter Array observations of GRO J1655-40 and LMC X-3 to explore the nature of the accretion disc via non-relativistic and relativistic disc models describing the thermal emission in black hole X-ray binaries. We demonstrate that the non-relativistic modelling throughout an outburst with the phenomenological multicolour disc model DISKBB yields significantly lower and often unphysical inner disc radii and correspondingly higher (& SIM, 50-60 per cent) disc temperatures compared to its relativistic counterparts KYNBB and KERRBB. We obtained the dimensionless spin parameters of a(*) = 0.774 & PLUSMN, 0.069 and a(*) = 0.752 & PLUSMN, 0.061 for GRO J1655-40 with KERRBB and KYNBB, respectively. We report a spin value of a(*) = 0.098 & PLUSMN, 0.063 for LMC X-3 using the updated black hole mass of 6.98 M-& ODOT. Both measurements are consistent with the previous studies. Using our results, we highlight the importance of self-consistent modelling of the thermal emission, especially when estimating the spin with the continuum-fitting method which assumes the disc terminates at the innermost stable circular orbit at all times.
Trvalý link: https://hdl.handle.net/11104/0345912