Evolving optical polarisation of the black hole X-ray binary MAXI J1820+070

Aims. The optical emission of black hole transients increases by several magnitudes during the X-ray outbursts. Whether the extra light arises from the X-ray heated outer disc, from the inner hot accretion flow, or from the jet is currently debated. Optical polarisation measurements are able to distinguish the relative contributions of these components. Methods. We present the results of BVR polarisation measurements of the black hole X-ray binary MAXI J1820+070 during the period of March-April 2018. Results. We detect small, ∼0.7%, but statistically significant polarisation, part of which is of interstellar origin. Depending on the interstellar polarisation estimate, the intrinsic polarisation degree of the source is between ∼0.3% and 0.7%, and the polarisation position angle is between ∼10 ° −30°. We show that the polarisation increases after MJD 58222 (2018 April 14). The change is of the order of 0.1% and is most pronounced in the R band. The change of the source Stokes parameters occurs simultaneously with the drop of the observed V-band flux and a slow softening of the X-ray spectrum. The Stokes vectors of intrinsic polarisation before and after the drop are parallel, at least in the V and R filters. Conclusions. We suggest that the increased polarisation is due to the decreasing contribution of the non-polarized component, which we associate with the the hot flow or jet emission. The low polarisation can result from the tangled geometry of the magnetic field or from the Faraday rotation in the dense, ionised, and magnetised medium close to the black hole. The polarized optical emission is likely produced by the irradiated disc or by scattering of its radiation in the optically thin outflow.

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Thermal and radiation driving can produce observable disc winds in hard-state X-ray binaries

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa209 ◽

2020 ◽

Vol 492 (4) ◽

pp. 5271-5279 ◽

Cited By ~ 2

Author(s):

Nick Higginbottom ◽

Christian Knigge ◽

Stuart A Sim ◽

Knox S Long ◽

James H Matthews ◽

...

Keyword(s):

Black Hole ◽

Binary Systems ◽

Velocity Structure ◽

Spectral Energy ◽

X Ray ◽

Black Hole Binaries ◽

Soft State ◽

Before And After ◽

Hard State ◽

New Generation

ABSTRACT X-ray signatures of outflowing gas have been detected in several accreting black hole binaries, always in the soft state. A key question raised by these observations is whether these winds might also exist in the hard state. Here, we carry out the first full-frequency radiation hydrodynamic simulations of luminous (${L = 0.5 \, L_{\mathrm{\mathrm{ Edd}}}}$) black hole X-ray binary systems in both the hard and the soft state, with realistic spectral energy distributions (SEDs). Our simulations are designed to describe X-ray transients near the peak of their outburst, just before and after the hard-to-soft state transition. At these luminosities, it is essential to include radiation driving, and we include not only electron scattering, but also photoelectric and line interactions. We find powerful outflows with ${\dot{M}_{\mathrm{ wind}} \simeq 2 \, \dot{M}_{\mathrm{ acc}}}$ are driven by thermal and radiation pressure in both hard and soft states. The hard-state wind is significantly faster and carries approximately 20 times as much kinetic energy as the soft-state wind. However, in the hard state the wind is more ionized, and so weaker X-ray absorption lines are seen over a narrower range of viewing angles. Nevertheless, for inclinations ≳80°, blueshifted wind-formed Fe xxv and Fe xxvi features should be observable even in the hard state. Given that the data required to detect these lines currently exist for only a single system in a luminous hard state – the peculiar GRS 1915+105 – we urge the acquisition of new observations to test this prediction. The new generation of X-ray spectrometers should be able to resolve the velocity structure.

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Recent Ginga Results on Galactic X-Ray Binaries

Highlights of Astronomy ◽

10.1017/s1539299600008947 ◽

1992 ◽

Vol 9 ◽

pp. 211-215

Author(s):

Y. Tanaka

Keyword(s):

Magnetic Field ◽

Black Hole ◽

Chandra Observations of the Guitar Nebula

Symposium - International Astronomical Union ◽

10.1017/s0074180900194276 ◽

2003 ◽

Vol 214 ◽

pp. 135-136 ◽

Cited By ~ 3

Author(s):

Diane S. Wong ◽

James M. Cordes ◽

Shami Chatterjee ◽

Ellen G. Zweibel ◽

John P. Finley ◽

...

Keyword(s):

Proper Motion ◽

Hot Spot ◽

Optical Emission ◽

Position Angle ◽

Bow Shock ◽

Radio Pulsar ◽

X Ray ◽

Multi Wavelength ◽

Pulsar Wind

As part of a multi-wavelength study, we report on a 50 ks Chandra/ACIS observation of the Guitar Nebula, a bow shock nebula associated with the radio pulsar B2224+65. We see a “hot spot” at the tip of the bow shock. We also notice a “jet” of X-ray emission at position angle (PA) −69°. However, the proper motion of the pulsar and the axis of optical emission is at PA 52°.1. We discuss the resulting interpretations of the relativistic pulsar wind and the surrounding ISM.

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Magnetized black hole as an accelerator of charged particle

10.20944/preprints202106.0302.v1 ◽

2021 ◽

Author(s):

Bobur Turimov

Keyword(s):

Magnetic Field ◽

Black Hole ◽

Charged Particle ◽

Active Galactic Nuclei ◽

Zeeman Effect ◽

Galactic Nuclei ◽

X Ray ◽

Fundamental Frequencies ◽

The Magnetic Field ◽

Relativistic Particles

Astrophysical accretion processes near the black hole candidates, such as active galactic nuclei (AGN), X-ray binary (XRB), and other astrophysical sources, are associated with high-energetic emission of radiation of relativistic particles and outflows (winds and/or jets). It is widely believed that the magnetic field plays a very important role to explain such high energetic processes in the vicinity of those astrophysical sources. In the present research note, we propose that the black hole is embedded in an asymptotically uniform magnetic field. We investigate the dynamical motion of charged particles in the vicinity of a weakly magnetized black hole. We show that in the presence of the magnetic field, the radius of the innermost stable circular orbits (ISCO) for a charged particle is located close to the black hole’s horizon. The fundamental frequencies, such as Keplerian and epicyclic frequencies of the charged particle are split into two parts due to the magnetic field, as an analog of the Zeeman effect. The orbital velocity of the charged particle measured by a local observer has been computed in the presence of the external magnetic field. We also present an analytical expression for the four-acceleration of the charged particle orbiting around black holes. Finally, we determine the intensity of the radiating charged accelerating relativistic particle orbiting around the magnetized black hole.

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Disc and wind in black hole X-ray binary MAXI J1820+070 observed through polarized light during its 2018 outburst

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/slaa096 ◽

2020 ◽

Vol 496 (1) ◽

pp. L96-L100

Author(s):

Ilia A Kosenkov ◽

Alexandra Veledina ◽

Andrei V Berdyugin ◽

Vadim Kravtsov ◽

Vilppu Piirola ◽

...

Keyword(s):

Black Hole ◽

Polarized Light ◽

Position Angle ◽

Intrinsic Polarization ◽

Data Set ◽

X Ray ◽

Soft State ◽

Hard State ◽

Low Mass ◽

Optical Flux

ABSTRACT We describe the first complete polarimetric data set of the entire outburst of a low-mass black hole X-ray binary system and discuss the constraints for geometry and radiative mechanisms it imposes. During the decaying hard state, when the optical flux is dominated by the non-thermal component, the observed polarization is consistent with the interstellar values in all filters. During the soft state, the intrinsic polarization of the source is small, ∼0.15 per cent in B and V filters, and is likely produced in the irradiated disc. A much higher polarization, reaching ∼0.5 per cent in V and R filters, at a position angle of ∼25○ observed in the rising hard state coincides in time with the detection of winds in the system. This angle coincides with the position angle of the jet. The detected optical polarization is best explained by scattering of the non-thermal (hot flow or jet base) radiation in an equatorial wind.

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Stellar X-Ray Sources

Symposium - International Astronomical Union ◽

10.1017/s0074180900026711 ◽

1974 ◽

Vol 60 ◽

pp. 383-399

Author(s):

Harvey D. Tananbaum

Keyword(s):

Black Hole ◽

Radio Emission ◽

Optical Emission ◽

Close Correlation ◽

X Ray ◽

Radio Outburst ◽

The Relationship ◽

Optical Behavior

Data are presented for Cygnus X-1, Cygnus X-3, and Scorpius X-1 from radio to X-ray wavelengths. The evidence for Cygnus X-1's being a black hole is now quite convincing. New data for Cygnus X-3 show the presence of X-ray activity at the time of the giant radio outburst. The data for Scorpius X-1 show a close correlation between the X-ray and optical behavior, but coverage was not sufficiently complete to fully assess the relationship (if any) between the X-ray and optical emission and the radio emission.

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Reactivity of Metakaolin in Alkaline Environment: Correlation of Results from Dissolution Experiments with XRD Quantifications

Materials ◽

10.3390/ma13102214 ◽

2020 ◽

Vol 13 (10) ◽

pp. 2214

Author(s):

Sebastian Scherb ◽

Mathias Köberl ◽

Nancy Beuntner ◽

Karl-Christian Thienel ◽

Jürgen Neubauer

Keyword(s):

Inductively Coupled Plasma ◽

Optical Emission ◽

Systematic Investigation ◽

Attenuated Total Reflection ◽

Emission Spectrometry ◽

Alkaline Solutions ◽

X Ray ◽

Inductively Coupled ◽

Before And After ◽

Congruent Dissolution

Systematic investigation of filtrates and filter residues resulting from a 24 h treatment of metakaolin in different alkaline solutions were performed. On filtered metakaolin particles, inductively coupled plasma-optical emission spectrometry (ICP-OES) measurements reveal an enrichment of iron and titanium, which suggests an inhomogeneous distribution of these cations. Since the SiO2/Al2O3 ratio remains constant in all filter residues examined, the dissolution of the Si and Al monomers is congruent. Structural differences, identified by attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR) as a consequence of alkali uptake, influence the X-ray scattering contribution of metakaolin, and thus quantifications with the partial or no known crystal structure (PONKCS) method. This leads to deviations between the degree of reaction calculated from Si and Al solubility from filtrate and that quantified by quantitative powder X-ray diffraction (QPXRD) using the filter residue. Nevertheless, the described changes do not cause a shift in the X-ray amorphous hump in case of congruent dissolution, and thus allow the quantification of the metakaolin before and after dissolution with the same hkl-phase model.

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Inverse Mapping of Pulsar Magnetospheres: Optical Emission Comes From 300 km Above the Surface

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312000877 ◽

2011 ◽

Vol 7 (S285) ◽

pp. 303-305

Author(s):

Diarmaid de Búrca ◽

Padraig O'Connor ◽

John McDonald ◽

Andy Shearer

Keyword(s):

Optical Emission ◽

Stokes Parameters ◽

Line Of Sight ◽

Crab Pulsar ◽

Inverse Mapping ◽

Computational Implementation ◽

Optical Photons ◽

The Magnetic Field ◽

Field Inclination ◽

Emission Height

AbstractIn order to determine the emission height of the optical photons from pulsars we present an inverse mapping approach, which is directly constrained by empirical data. The model discussed is for the case of the Crab pulsar. Our method, which uses the optical Stokes parameters, determines the most likely geometry for emission including the magnetic-field inclination angle (α), the observer's line-of-sight angle (χ) and emission height. We discuss the computational implementation of the approach, and the physical assumptions made. We find that the most likely emission altitude is at 20% of the light-cylinder radius above the stellar surface in the open field region.

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The Cosmic History of Black Hole Growth from Deep Multiwavelength Surveys

Advances in Astronomy ◽

10.1155/2012/516193 ◽

2012 ◽

Vol 2012 ◽

pp. 1-21 ◽

Cited By ~ 15

Author(s):

Ezequiel Treister ◽

C. Megan Urry

Keyword(s):

Black Holes ◽

Black Hole ◽

Optical Emission ◽

Supermassive Black Holes ◽

X Ray ◽

Open Questions ◽

Black Hole Growth ◽

History Of ◽

Hole Growth ◽

Cosmic History

Significant progress has been made in the last few years on understanding how supermassive black holes form and grow. In this paper, we begin by reviewing the spectral signatures of active galactic nuclei (AGN) ranging from radio to hard X-ray wavelengths. We then describe the most commonly used methods to find these sources, including optical/UV, radio, infrared, and X-ray emission, and optical emission lines. We then describe the main observational properties of the obscured and unobscured AGN population. Finally, we summarize the cosmic history of black hole accretion, that is, when in the history of the universe supermassive black holes were getting most of their mass. We finish with a summary of open questions and a description of planned and future observatories that are going to help answer them.

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CONSTRAINTS ON X-RAY POLARIZATION OF SYNCHROTRON JETS FROM STELLAR-MASS BLACK HOLES

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512004473 ◽

2012 ◽

Vol 08 ◽

pp. 102-107

Author(s):

D. M. RUSSELL

Keyword(s):

Magnetic Field ◽

Black Holes ◽

Black Hole ◽

Synchrotron Emission ◽

Relativistic Jets ◽

X Ray ◽

Linearly Polarized ◽

Hard State ◽

X Ray Binaries ◽

The Magnetic Field

For most black hole X-ray binaries, the fraction of X-ray flux originating in the synchrotron jets is generally thought to be low in the hard state. However in one intriguing case, the infrared – X-ray correlations, evolution of broadband spectra and timing signatures suggest that synchrotron emission from a jet likely dominated both the infrared and X-ray flux on the hard state decline of an outburst of XTE J1550–564 at a luminosity of ~ (2 × 10-4 – 2 × 10-3) L Edd . Synchrotron emission from the relativistic jets launched close to black holes can be highly linearly polarized, depending on the configuration of the magnetic field. It has recently been shown that the polarimetric signature of their jets is detected in the infrared and is highly variable. This reveals the magnetic geometry in a region of the compact jet near its base, close to the black hole. From these results, it is predicted that in some cases, high (possibly up to 10%), variable levels of X-ray polarization from synchrotron emission originating in jets will be detected from accreting black holes by future spaceborne X-ray polarimeters.

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