The effect of advection at luminosities close to Eddington: The ULX in M31

Abstract

The transient, ultra-luminous X-ray source CXOM31 J004253.1+411422 in the Andromeda galaxy is most likely a 10 solar mass black hole, with super-Eddington luminosity at its peak. The XMM-Newton spectra taken during the decline then trace luminosities of 0.86-0.27 L_Edd. These spectra are all dominated by a hot disc component, which roughly follows a constant inner radius track in luminosity and temperature as the source declines. At the highest luminosity the disc structure should change due to advection of radiation through the disc. This advected flux can be partly released at lower radii thus modifying the spectral shape. To study the effect of advection at luminosities close to Eddington we employ a fully relativistic slim disc model, SLIMBH, that includes advective cooling and full radiative transfer through the photosphere based on TLUSTY. The model also incorporates relativistic photon ray-tracing from the proper location of the disc photosphere rather than the mid-plane as the slim disc is no longer geometrically thin. We find that these new models differ only slightly from the non-advective (standard) BHSPEC models even at the highest luminosities considered here. While both discs can fit the highest luminosity data, neither is a very good fit to the *lower* luminosities. This could indicate a missing physical process that acts in low luminosity discs and subsides as the disc luminosity approaches the Eddington limit.

5 pages, 4 figures, improved figures

References in corpus (10)

• Super-critically accreting stellar-mass black holes as ultraluminous X-ray sources
• Accretion disc viscosity: how big is alpha?
• Slim disks around Kerr black holes revisited
• A Grid of Relativistic, non-LTE Accretion Disk Models for Spectral Fitting of Black Hole Binaries
• Accretion Discs with Strong Toroidal Magnetic Fields
• The Eye of the Storm: Light from the Inner Plunging Region of Black Hole Accretion Discs
• The missing link: a low mass X-ray binary in M31 seen as an ultraluminous X-ray source
• Angular Momentum Transport in Accretion Disks and its Implications for Spin Estimates in Black Hole Binaries
• Saturation of the MRI in Strongly Radiation Dominated Accretion Disks
• CXOM31 J004253.1+411422: The first ultra-luminous X-ray transient in M 31

Cited by in corpus (16)

• Ultraluminous X-Ray Sources
• A spectral-timing model for ULXs in the super-critical regime
• The ultraluminous X-ray sources NGC 1313 X-1 and X-2: a broadband study with NuSTAR and XMM-Newton
• Ultraluminous X-ray sources
• Diagnosing the accretion flow in ultraluminous X-ray sources using soft X-ray atomic features
• ULX spectra revisited: Accreting, highly magnetized neutron stars as the engines of ultraluminous X-ray sources
• Living on a Flare: Relativistic Reflection in V404 Cyg Observed by NuSTAR During its Summer 2015 Outburst
• A new way to measure supermassive black hole spin in accretion disc dominated Active Galaxies
• Testing wind as an explanation for the spin problem in the continuum-fitting method
• Black hole spin: theory and observation
• Investigating the mass of the intermediate mass black hole candidate HLX-1 with the SLIMBH model
• Doppler disc tomography applied to low mass AGN spin
• Crossing the Eddington limit: examining disk spectra at high accretion rates
• Black hole mass and spin estimates of the most distant quasars
• Revealing the nature of the ULX and X-ray population of the spiral galaxy NGC 4088
• Ultraluminous X-ray sources in the group-centric elliptical galaxy NGC 5813