The Nature of ULX Source M101 X-1: Optically Thick Outflow from A Stellar Mass Black Hole

Abstract

The nature of ultra-luminous X-ray sources (ULXs) has long been plagued by an ambiguity about whether the central compact objects are intermediate-mass (IMBH, >~ 10^3 M_sun) or stellar-mass (a few tens M_sun) black holes (BHs). The high luminosity (~ 10^39 erg/s) and super-soft spectrum (T ~ 0.1 keV) during the high state of the ULX source X-1 in the galaxy M101 suggest a large emission radius (>~ 10^9 cm), consistent with being an IMBH accreting at a sub-Eddington rate. However, recent kinematic measurement of the binary orbit of this source and identification of the secondary as a Wolf-Rayet star suggest a stellar-mass BH primary with a super-Eddington accretion. If that is the case, a hot, optically thick outflow from the BH can account for the large emission radius and the soft spectrum. By considering the interplay of photons' absorption and scattering opacities, we determine the radius and mass density of the emission region of the outflow and constrain the outflow mass loss rate. The analysis presented here can be potentially applied to other ULXs with thermally dominated spectra, and to other super-Eddington accreting sources.

arXiv comment5 pages, 1 figure. Added two references. Accepted by MNRAS Letters

References in corpus (6)

• A high velocity ionised outflow and XUV photosphere in the narrow emission line quasar PG1211+143
• Black Hole Winds
• Puzzling accretion onto a black hole in the ultraluminous X-ray source M101 ULX-1
• Broad absorption features in wind-dominated ULXs?
• Evidence for an Intermediate-Mass Black Hole: Chandra and XMM-Newton Observations of the Ultraluminous Supersoft X-ray Source in M101 during its 2004 Outburst
• The X-ray Properties of M101 ULX-1 = CXOKM101 J140332.74+542102

Cited by in corpus (27)

• A spectral-timing model for ULXs in the super-critical regime
• Optically thick outflows in ultraluminous supersoft sources
• Understanding the high-mass binary black hole population from stable mass transfer and super-Eddington accretion in BPASS
• Wind-reprocessed Transients
• Nature of the soft ULX in NGC 247: super-Eddington outflow and transition between the supersoft and soft ultraluminous regimes
• Super-Eddington accretion onto the Galactic ultraluminous X-ray pulsar Swift J0243.6+6124
• On rapid binary mass transfer -- I. Physical model
• A Super-Eddington Compton-Thick Wind in GRO J1655-40?
• Revisiting the ultraluminous supersoft source in M101: an optically thick outflow model
• Evidence for precession due to supercritical accretion in ultraluminous X-ray sources
• Relativistic baryonic jets from an ultraluminous supersoft X-ray source
• Evidence for Optically Thick, Eddington-limited Winds Driven by Supercritical Accretion
• Limits on mass outflow from optical tidal disruption events
• Statistical study of a large and cleaned sample of ultraluminous and hyperluminous X-ray sources
• Ultraluminous X-ray sources: three exciting years
• Thick Accretion Disk Model for Ultraluminous Supersoft Sources
• The chameleon on the branches: spectral state transition and dips in NGC 247 ULX-1
• X-ray outbursts of ESO 243-49 HLX-1: comparison with Galactic low-mass X-ray binary transients
• The dynamics of radiation driven, optically thick winds
• Swift J1644+57: an Ideal Test Bed of Radiation Mechanisms in a Relativistic Super-Eddington Jet
• Optical/UV Emission in the Tidal Disruption Event ASASSN-14li: Implications of Disc Modeling
• Vertical Advection Effects on Hyper-accretion Disks and Potential Link between Gamma-ray Bursts and Kilonovae
• Discovery of two eclipsing X-ray binaries in M51
• Comparison of different Tidal Disruption Event light curve models with TiDE, a new modular open source code
• External inverse-Compton emission from jetted tidal disruption events
• The spectra of a radiative reprocessing outflow model for fast blue optical transients
• Probing spectral variability in NGC 4490 ULX-8 over 24 years of XMM-Newton, Chandra and Swift-XRT observations