A magnetic accretion disk-outflow model for state transition in X-ray binaries

Abstract

The hard to soft state transition of the outbursts in X-ray binaries (XRBs) is triggered by the rising of the mass accretion rate due to the disk instability. In order to explain the observed correlation between the hard X-ray transition luminosity and the soft X-ray peak luminosity in the soft state, we construct a magnetic disk-outflow model for the state transition in XRBs. We assume that the large-scale magnetic field in the outer thin disk is formed through inverse cascade of small-scale dynamo generated field, and it is then advected by the inner advection dominated accretion flow (ADAF), which accelerates a fraction of the gas into the outflows. During the outbursts, the heating front moves inwards, and the field strength at the heating front of the outer disk is proportional to the accretion rate of the disk. Much angular momentum of the inner ADAF is carried away by the outflows for a stronger magnetic field, which leads to a high radial velocity of the ADAF. This makes the critical mass accretion rate of the ADAF increases with the field strength, and it therefore leads to a correlation between transition luminosity and the peak luminosity in the thermal state. We found that the values of the viscosity parameter $\alpha$ of the neutron star XRBs are systematically higher for those of the black hole (BH) XRBs ($\alpha \sim 0.05-0.15$ for BHs, and $\alpha \sim 0.15-0.4$ for neutron stars). Our model predicts the transition luminosity may be higher than the peak luminosity provided $\alpha$ is sufficiently high, which is able to explain a substantial fraction of outbursts in BHXRBs not reaching the thermally dominant accretion state.

arXiv commentaccepted by A&A, 7 pages

References in corpus (43)

• Advection-Dominated Accretion: A Self-Similar Solution
• Advection-Dominated Accretion: Underfed Black Holes and Neutron Stars
• Hot Accretion Flows Around Black Holes
• Advection-Dominated Accretion and the Spectral States of Black Hole X-Ray Binaries: Application to Nova Muscae 1991
• The disc instability model for X-ray transients: evidence for truncation and irradiation
• WATCHDOG: A Comprehensive All-Sky Database of Galactic Black Hole X-ray Binaries
• States and transitions in black-hole binaries
• X-ray irradiation in low mass binary systems
• Extracting energy from black holes: the relative importance of the Blandford-Znajek mechanism
• GX 339-4: the distance, state transitions, hysteresis and spectral correlations
• Hysteresis in the Light Curves of Soft X-ray Transients
• X-ray Reflection Spectroscopy of the Black Hole GX 339-4: Exploring the Hard State with Unprecedented Sensitivity
• Large-Scale Poloidal Magnetic Field Dynamo Leads to Powerful Jets in GRMHD Simulations of Black Hole Accretion with Toroidal Field
• Transport of Large Scale Poloidal Flux in Black Hole Accretion
• Global Evolution of an Accretion Disk with Net Vertical Field: Coronal Accretion, Flux Transport, and Disk Winds
• A unified accretion-ejection paradigm for Black Hole X-ray Binaries
• The 1996 Soft State Transitions of Cygnus X-1
• Variability in black hole accretion discs
• The hard X-ray spectral evolution in X-ray binaries and its application to constrain the black hole mass of ultraluminous X-ray sources
• Coronal--Temporal Correlations in GX339-4: Hysteresis, Possible Reflection Changes, and Implications for ADAFs
• Strong disc winds traced throughout outbursts in black-hole X-ray binaries
• The large scale magnetic fields of advection dominated accretion flows
• The large scale magnetic fields of thin accretion disks
• Orbital Period and Outburst Luminosity of Transient Low Mass X-ray Binaries
• X-ray outbursts of low-mass X-ray binary transients observed in the RXTE era
• State Transitions in Bright Galactic X-ray Binaries: Luminosities Span by Two Orders of Magnitude
• Hot accretion discs with thermal Comptonisation and advection in luminous black hole sources
• Instability of an accretion disk with a magnetically driven wind
• Events leading up to the June 2015 outburst of V404 Cyg
• Correlation between Hard X-ray Peak Flux and Soft X-ray Peak Flux in the Outburst Rise of Low Mass X-ray Binaries
• Thermal stability of thin disk with magnetically driven winds
• A NICER look at the state transitions of the black hole candidate MAXI J1535-571 during its reflares
• Strongly magnetized accretion discs require poloidal flux
• Peak Luminosities of the Hard States of GX 339-4: Implications for the Accretion Geometry, Disk Mass, and Black Hole Mass
• An accretion disk-outflow model for hysteretic state transition in X-ray binaries
• Detection of X-ray spectral state transitions in mini-outbursts of black hole transient GRS 1739-278
• The large-scale magnetic field of a thin accretion disk with outflows
• A Hard-to-Soft State Transition during A Luminosity Decline of Aquila X-1
• Revisit the fundamental plane of black-hole activity from sub-Eddington to quiescent state
• Different X-ray spectral evolution for black hole X-ray binaries in dual tracks of radio-X-ray correlation
• Searching for a magnetic field in Wolf-Rayet stars using FORS2 spectropolarimetry
• The high efficiency jets magnetically accelerated from a thin disk in powerful lobe-dominated FRII radio galaxies
• Jets in the soft state in Cyg X-3 caused by advection of the donor magnetic field and unification with low-mass X-ray binaries