A Variable Ultraluminous Supersoft X‐Ray Source in “The Antennae”: Stellar‐Mass Black Hole or White Dwarf?

AbstractRelationships between the X-ray and radio behavior of black hole X-ray binaries during outbursts have established a fundamental coupling between the accretion disks and radio jets in these systems. I begin by reviewing the prevailing paradigm for this disk-jet coupling, also highlighting what we know about similarities and differences with neutron star and white dwarf binaries. Until recently, this paradigm had not been directly tested with dedicated high-angular resolution radio imaging over entire outbursts. Moreover, such high-resolution monitoring campaigns had not previously targetted outbursts in which the compact object was either a neutron star or a white dwarf. To address this issue, we have embarked on the Jet Acceleration and Collimation Probe Of Transient X-Ray Binaries (JACPOT XRB) project, which aims to use high angular resolution observations to compare disk-jet coupling across the stellar mass scale, with the goal of probing the importance of the depth of the gravitational potential well, the stellar surface and the stellar magnetic field, on jet formation. Our team has recently concluded its first monitoring series, including (E)VLA, VLBA, X-ray, optical, and near-infrared observations of entire outbursts of the black hole candidate H 1743-322, the neutron star system Aquila X-1, and the white dwarf system SS Cyg. Here I present preliminary results from this work, largely confirming the current paradigm, but highlighting some intriguing new behavior, and suggesting a possible difference in the jet formation process between neutron star and black hole systems.

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Probing black hole accretion tracks, scaling relations, and radiative efficiencies from stacked X-ray active galactic nuclei

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3522 ◽

2019 ◽

Vol 493 (1) ◽

pp. 1500-1511 ◽

Cited By ~ 9

Author(s):

Francesco Shankar ◽

David H Weinberg ◽

Christopher Marsden ◽

Philip J Grylls ◽

Mariangela Bernardi ◽

...

Keyword(s):

Black Holes ◽

Black Hole ◽

Selection Bias ◽

Stellar Mass ◽

Supermassive Black Holes ◽

Independent Evidence ◽

X Ray ◽

Black Hole Accretion ◽

Black Hole Masses ◽

Hole Accretion

ABSTRACT The masses of supermassive black holes at the centres of local galaxies appear to be tightly correlated with the mass and velocity dispersions of their galactic hosts. However, the local Mbh–Mstar relation inferred from dynamically measured inactive black holes is up to an order-of-magnitude higher than some estimates from active black holes, and recent work suggests that this discrepancy arises from selection bias on the sample of dynamical black hole mass measurements. In this work, we combine X-ray measurements of the mean black hole accretion luminosity as a function of stellar mass and redshift with empirical models of galaxy stellar mass growth, integrating over time to predict the evolving Mbh–Mstar relation. The implied relation is nearly independent of redshift, indicating that stellar and black hole masses grow, on average, at similar rates. Matching the de-biased local Mbh–Mstar relation requires a mean radiative efficiency ε ≳ 0.15, in line with theoretical expectations for accretion on to spinning black holes. However, matching the ‘raw’ observed relation for inactive black holes requires ε ∼ 0.02, far below theoretical expectations. This result provides independent evidence for selection bias in dynamically estimated black hole masses, a conclusion that is robust to uncertainties in bolometric corrections, obscured active black hole fractions, and kinetic accretion efficiency. For our fiducial assumptions, they favour moderate-to-rapid spins of typical supermassive black holes, to achieve ε ∼ 0.12–0.20. Our approach has similarities to the classic Soltan analysis, but by using galaxy-based data instead of integrated quantities we are able to focus on regimes where observational uncertainties are minimized.

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Warm and thick corona for a magnetically supported disk in galactic black hole binaries

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935033 ◽

2020 ◽

Vol 633 ◽

pp. A35 ◽

Cited By ~ 4

Author(s):

D. Gronkiewicz ◽

A. Różańska

Keyword(s):

Magnetic Field ◽

Black Hole ◽

Accretion Disk ◽

Thermal Instability ◽

Stellar Mass ◽

Rotational Instability ◽

X Ray ◽

Black Hole Binaries ◽

Radiative Processes ◽

Gas Heating

Context. We self-consistently model a magnetically supported accretion disk around a stellar-mass black hole with a warm optically thick corona based on first principles. We consider the gas heating by magneto-rotational instability dynamo. Aims. Our goal is to show that the proper calculation of the gas heating by magnetic dynamo can build up the warm optically thick corona above the accretion disk around a black hole of stellar mass. Methods. Using the vertical model of the disk supported and heated by the magnetic field together with radiative transfer in hydrostatic and radiative equilibrium, we developed a relaxation numerical scheme that allowed us to compute the transition form the disk to corona in a self-consistent way. Results. We demonstrate here that the warm (up to 5 keV) optically thick (up to 10 τes) Compton-cooled corona can form as a result of magnetic heating. A warm corona like this is stronger in the case of the higher accretion rate and the greater magnetic field strength. The radial extent of the warm corona is limited by local thermal instability, which purely depends on radiative processes. The obtained coronal parameters are in agreement with those constrained from X-ray observations. Conclusions. A warm magnetically supported corona tends to appear in the inner disk regions. It may be responsible for soft X-ray excess seen in accreting sources. For lower accretion rates and weaker magnetic field parameters, thermal instability prevents a warm corona, giving rise to eventual clumpiness or ionized outflow.

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Observational evidence for stellar-mass black holes

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307004590 ◽

2006 ◽

Vol 2 (S238) ◽

pp. 3-12 ◽

Cited By ~ 4

Author(s):

Jorge Casares

Keyword(s):

Black Holes ◽

Black Hole ◽

Mass Spectrum ◽

Radial Velocity ◽

Stellar Mass ◽

Observational Evidence ◽

X Ray ◽

History Of ◽

X Ray Binaries ◽

Dynamical Masses

AbstractRadial velocity studies of X-ray binaries provide the most solid evidence for the existence of stellar-mass black holes. We currently have 20 confirmed cases, with dynamical masses in excess of 3 M⊙. Accurate masses have been obtained for a subset of systems which gives us a hint at the mass spectrum of the black hole population. This review summarizes the history of black hole discoveries and presents the latest results in the field.

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Galactic X- ray observations - Observations of compact X-ray sources

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1979.0052 ◽

1979 ◽

Vol 366 (1726) ◽

pp. 281-293 ◽

Cited By ~ 1

Keyword(s):

Black Hole ◽

Neutron Star ◽

White Dwarf ◽

Compact Object ◽

Bright Star ◽

High Luminosity ◽

Multiple Star ◽

X Ray ◽

Normal Star ◽

Radio Outburst

The high luminosity galactic X-ray sources, apart from the supernovae remnants, probably all exist in multiple star systems in which matter from a normal star is being transferred to a compact object such as a white dwarf, neutron star or black hole. Recent results, obtained with the Ariel 5 and Copernicus satellites, are presented. A number of sources have been studied over extended periods in order to measure the regular periodicities in their X-ray emission. Observations also included are of the Cygnus X-1 source, which is probably the first black hole discovered in our galaxy. X-ray emission, coincident with a radio outburst, from a nearby bright star HR1099 is also reported.

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Possibility of a White Dwarf as the Accreting Compact Star in CI Cam (XTE J0421+560)

International Astronomical Union Colloquium ◽

10.1017/s025292110015208x ◽

2004 ◽

Vol 194 ◽

pp. 104-105

Author(s):

Manabu Ishida ◽

Kazuyuki Morio ◽

Yoshihiro Ueda

Keyword(s):

Black Hole ◽

White Dwarf ◽

Compact Star ◽

X Ray

AbstractAlthough CI Cam, which showed an outburst in April 1998, has been regarded as a soft X-ray transient (SXT) harboring a, black hole, it has some characteristics that can hardly be reconciled with the SXT picture. In this paper, we propose a white dwarf as the central accreting star in CI Cam.

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Radio and X-ray detections of GX 339–4 in quiescence using MeerKAT and Swift

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/slaa019 ◽

2020 ◽

Vol 493 (1) ◽

pp. L132-L137 ◽

Cited By ~ 3

Author(s):

E Tremou ◽

S Corbel ◽

R P Fender ◽

P A Woudt ◽

J C A Miller-Jones ◽

...

Keyword(s):

Black Holes ◽

Black Hole ◽

Active Galactic Nuclei ◽

Binary Systems ◽

Accretion Rate ◽

Galactic Nuclei ◽

Stellar Mass ◽

X Ray ◽

Accretion Process ◽

Upper Limits

ABSTRACT The radio–X-ray correlation that characterizes accreting black holes at all mass scales – from stellar mass black holes in binary systems to supermassive black holes powering active galactic nuclei – is one of the most important pieces of observational evidence supporting the existence of a connection between the accretion process and the generation of collimated outflows – or jets – in accreting systems. Although recent studies suggest that the correlation extends down to low luminosities, only a handful of stellar mass black holes have been clearly detected, and in general only upper limits (especially at radio wavelengths) can be obtained during quiescence. We recently obtained detections of the black hole X-ray binary (XRB) GX 339–4 in quiescence using the Meer Karoo Array Telescope (MeerKAT) radio telescope and Swift X-ray Telescope instrument on board the Neil Gehrels Swift Observatory, probing the lower end of the radio–X-ray correlation. We present the properties of accretion and of the connected generation of jets in the poorly studied low-accretion rate regime for this canonical black hole XRB system.

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Stellar-mass black hole binaries as ultraluminous X-ray sources

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2004.08489.x ◽

2005 ◽

Vol 356 (2) ◽

pp. 401-414 ◽

Cited By ~ 87

Author(s):

S. A. Rappaport ◽

Ph. Podsiadlowski ◽

E. Pfahl

Keyword(s):

Black Hole ◽

Stellar Mass ◽

X Ray ◽

Black Hole Binaries

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Coevolution of black hole accretion and star formation in galaxies up to z = 3.5

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936649 ◽

2020 ◽

Vol 642 ◽

pp. A65

Author(s):

R. Carraro ◽

G. Rodighiero ◽

P. Cassata ◽

M. Brusa ◽

F. Shankar ◽

...

Keyword(s):

Black Holes ◽

Black Hole ◽

Star Formation ◽

Stellar Mass ◽

Starburst Galaxies ◽

Black Hole Mass ◽

X Ray ◽

Star Forming ◽

Black Hole Accretion ◽

Hole Accretion

Aims. We study the coevolution between the black hole accretion rate (BHAR) and the star formation rate (SFR) in different phases of galaxy life: main-sequence star-forming galaxies, quiescent galaxies, and starburst galaxies at different cosmic epochs. Methods. We exploited the unique combination of depth and area in the COSMOS field and took advantage of the X-ray data from the Chandra COSMOS-Legacy survey and the extensive multiwavelength ancillary data presented in the COSMOS2015 catalog, including in particular the UVista Ultra-deep observations. These large datasets allowed us to perform an X-ray stacking analysis and combine it with detected sources in a broad redshift interval (0.1 < z < 3.5) with unprecedented statistics for normal star-forming, quiescent, and starburst galaxies. The X-ray luminosity was used to predict the black holeAR, and a similar stacking analysis on far-infrared Herschel maps was used to measure the corresponding obscured SFR for statistical samples of sources in different redshifts and stellar mass bins. Results. We focus on the evolution of the average SFR-stellar mass (M*) relation and compare it with the BHAR-M* relation. This extends previous works that pointed toward the existence of almost linear correlations in both cases. We find that the ratio between BHAR and SFR does not evolve with redshift, although it depends on stellar mass. For the star-forming populations, this dependence on M* has a logarithmic slope of ∼0.6 and for the starburst sample, the slope is ∼0.4. These slopes are both at odds with quiescent sources, where the dependence remains constant (log(BHAR/SFR) ∼ −3.4). By studying the specific BHAR and specific SFR, we find signs of downsizing for M* and black hole mass (MBH) in galaxies in all evolutionary phases. The increase in black hole mass-doubling timescale was particularly fast for quiescents, whose super-massive black holes grew at very early times, while accretion in star-forming and starburst galaxies continued until more recent times. Conclusions. Our results support the idea that the same physical processes feed and sustain star formation and black hole accretion in star-forming galaxies while the starburst phase plays a lesser role in driving the growth of the supermassive black holes, especially at high redshift. Our integrated estimates of the M* − MBH relation at all redshifts are consistent with independent determinations of the local M* − MBH relation for samples of active galactic nuclei. This adds key evidence that the evolution in the BHAR/SFR is weak and its normalization is relatively lower than that of local dynamical M* − MBH relations.

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