Probing the accretion-jet physics with the radio∕X-ray correlation

2008 ◽  
Author(s):  
Xue-Bing Wu ◽  
R. Wang ◽  
Z. Y. Li ◽  
M. Z. Kong ◽  
Ye-Fei Yuan ◽  
...  
Keyword(s):  
Jet Physics ◽  
X Ray

scholarly journals Estimation of the jet inclination angle for the TDE Swift J1644+57

2019 ◽  
Vol 492 (2) ◽  
pp. 1634-1640
Author(s):  
Sudip Chakraborty ◽  
Sudip Bhattacharyya ◽  
Chandrachur Chakraborty ◽  
A R Rao
Keyword(s):  
Black Hole ◽  
Data Analysis ◽  
Inclination Angle ◽  
Jet Physics ◽  
Triggering Mechanism ◽  
Tidal Disruption ◽  
X Ray ◽  
Upper Limit ◽  
The One ◽  
Disruption Event

ABSTRACT An estimate of the jet inclination angle relative to the accreting black hole’s spin can be useful to probe the jet triggering mechanism and the disc–jet coupling. A tidal disruption event (TDE) of a star by a supermassive spinning black hole provides an excellent astrophysical laboratory to study the jet direction through the possibility of jet precession. In this work, we report a new method to constrain the jet inclination angle β and apply it to the well-sampled jetted TDE Swift J1644+57. This method involves X-ray data analysis and comparisons of jet models with broad properties of the observed X-ray dips, to estimate the upper limit of the extent of the contribution of a plausible jet precession to these X-ray dips. From this limit, we find that β is very likely to be less than ∼15° for Swift J1644+57. Such a well-constrained jet inclination angle could be useful to probe the jet physics. The main advantage of our method is that it does not need to assume an origin of the observed X-ray dips, and the conclusion does not depend on any particular type of jet precession (e.g. the one due to the Lense–Thirring effect) or any specific value of precession frequency or any particular jet model. These make this method reliable and applicable to other jetted TDEs, as well as to other jetted accreting systems.

scholarly journals First constraints on the AGN X-ray luminosity function at z ~ 6 from an eROSITA-detected quasar

2021 ◽  
Vol 647 ◽  
pp. A5
Author(s):  
J. Wolf ◽  
K. Nandra ◽  
M. Salvato ◽  
T. Liu ◽  
J. Buchner ◽  
...  
Keyword(s):  
Luminosity Function ◽  
Large Scale ◽  
High Redshift ◽  
Jet Physics ◽  
Selection Function ◽  
Source Population ◽  
X Rays ◽  
X Ray ◽  
Colour Parameter ◽  
Sky Survey

Context. High-redshift quasars signpost the early accretion history of the Universe. The penetrating nature of X-rays enables a less absorption-biased census of the population of these luminous and persistent sources compared to optical/near-infrared colour selection. The ongoing SRG/eROSITA X-ray all-sky survey offers a unique opportunity to uncover the bright end of the high-z quasar population and probe new regions of colour parameter space. Aims. We searched for high-z quasars within the X-ray source population detected in the contiguous ~140 deg2 field observed by eROSITA during the performance verification phase. With the purpose of demonstrating the unique survey science capabilities of eROSITA, this field was observed at the depth of the final all-sky survey. The blind X-ray selection of high-redshift sources in a large contiguous, near-uniform survey with a well-understood selection function can be directly translated into constraints on the X-ray luminosity function (XLF), which encodes the luminosity-dependent evolution of accretion through cosmic time. Methods. We collected the available spectroscopic information in the eFEDS field, including the sample of all currently known optically selected z > 5.5 quasars and cross-matched secure Legacy DR8 counterparts of eROSITA-detected X-ray point-like sources with this spectroscopic sample. Results. We report the X-ray detection of eFEDSU J083644.0+005459, an eROSITA source securely matched to the well-known quasar SDSS J083643.85+005453.3 (z = 5.81). The soft X-ray flux of the source derived from eROSITA is consistent with previous Chandra observations. The detection of SDSS J083643.85+005453.3 allows us to place the first constraints on the XLF at z > 5.5 based on a secure spectroscopic redshift. Compared to extrapolations from lower-redshift observations, this favours a relatively flat slope for the XLF at z ~ 6 beyond L*, the knee in the luminosity function. In addition, we report the detection of the quasar with LOFAR at 145 MHz and ASKAP at 888 MHz. The reported flux densities confirm a spectral flattening at lower frequencies in the emission of the radio core, indicating that SDSS J083643.85+005453.3 could be a (sub-) gigahertz peaked spectrum source. The inferred spectral shape and the parsec-scale radio morphology of SDSS J083643.85+005453.3 indicate that it is in an early stage of its evolution into a large-scale radio source or confined in a dense environment. We find no indications for a strong jet contribution to the X-ray emission of the quasar, which is therefore likely to be linked to accretion processes. Conclusions. Our results indicate that the population of X-ray luminous AGNs at high redshift may be larger than previously thought. From our XLF constraints, we make the conservative prediction that eROSITA will detect ~90 X-ray luminous AGNs at redshifts 5.7 < z < 6.4 in the full-sky survey (De+RU). While subject to different jet physics, both high-redshift quasars detected by eROSITA so far are radio-loud; a hint at the great potential of combined X-ray and radio surveys for the search of luminous high-redshift quasars.

scholarly journals Measuring fundamental jet properties with multi-wavelength fast timing of the black hole X-ray binary MAXI J1820+070

2021 ◽  
Author(s):  
A J Tetarenko ◽  
P Casella ◽  
J C A Miller-Jones ◽  
G R Sivakoff ◽  
J A Paice ◽  
...  
Keyword(s):  
Black Hole ◽  
Time Domain ◽  
New Technology ◽  
Time Domain Analysis ◽  
Jet Physics ◽  
Time Lags ◽  
Data Set ◽  
X Ray ◽  
Fast Timing ◽  
Multi Wavelength

Abstract We present multi-wavelength fast timing observations of the black hole X-ray binary MAXI J1820+070 (ASASSN-18ey), taken with the Karl G. Jansky Very Large Array (VLA), Atacama Large Millimeter/Sub-Millimeter Array (ALMA), Very Large Telescope (VLT), New Technology Telescope (NTT), Neutron Star Interior Composition Explorer (NICER), and XMM-Newton. Our data set simultaneously samples ten different electromagnetic bands (radio – X-ray) over a 7-hour period during the hard state of the 2018–2019 outburst. The emission we observe is highly variable, displaying multiple rapid flaring episodes. To characterize the variability properties in our data, we implemented a combination of cross-correlation and Fourier analyses. We find that the emission is highly correlated between different bands, measuring time-lags ranging from hundreds of milliseconds between the X-ray/optical bands to minutes between the radio/sub-mm bands. Our Fourier analysis also revealed, for the first time in a black hole X-ray binary, an evolving power spectral shape with electromagnetic frequency. Through modelling these variability properties, we find that MAXI J1820+070 launches a highly relativistic ($\Gamma =6.81^{+1.06}_{-1.15}$) and confined ($\phi =0.45^{+0.13}_{-0.11}$ deg) jet, which is carrying a significant amount of power away from the system (equivalent to ∼0.6 L1 − 100keV). We additionally place constraints on the jet composition and magnetic field strength in the innermost jet base region. Overall, this work demonstrates that time-domain analysis is a powerful diagnostic tool for probing jet physics, where we can accurately measure jet properties with time-domain measurements alone.

M 87 — TEN YEARS OF TEV GAMMA-RAY OBSERVATIONS

2010 ◽  
Vol 19 (06) ◽  
pp. 849-857
Author(s):  
MATTHIAS BEILICKE
Keyword(s):  
Active Galactic Nuclei ◽  
Gamma Ray ◽  
Radio Galaxy ◽  
Galactic Nuclei ◽  
Plasma Jet ◽  
Radio Galaxies ◽  
Jet Physics ◽  
X Ray ◽  
High Energies ◽  
Very High

The giant radio galaxy M 87 is located 16.7 Mpc away and harbours a supermassive black hole in its center. Structures of its relativistic plasma jet are resolved at radio, optical and X–ray energies. M 87 belongs to the class of active galactic nuclei and is one of only a few radio galaxies detected at very-high energies (E > 100 GeV ). This makes it a unique laboratory to study jet physics and the corresponding emission processes. The results obtained from TeV gamma-ray observations during the last decade are discussed.

scholarly journals Fitting along the Fundamental Plane: New comparisons of jet physics across the black hole mass scale

2010 ◽  
Vol 6 (S275) ◽  
pp. 250-254 ◽  
Author(s):  
Sera Markoff ◽  
Michael A. Nowak ◽  
Dipankar Maitra ◽  
Jörn Wilms ◽  
Elena Gallo ◽  
...  
Keyword(s):  
Black Hole ◽  
Mass Range ◽  
Mass Scale ◽  
Jet Physics ◽  
Black Hole Mass ◽  
Fundamental Plane ◽  
X Ray ◽  
Black Hole Accretion ◽  
Hard State ◽  
X Ray Binaries

AbstractCorrelations between the radio and X-ray bands in the hard state of black hole X-ray binaries (BHBs) have led to the discovery of the Fundamental Plane of black hole accretion, linking accretion-driven radiative attributes to black hole mass. Although this discovery has led to new constraints on radiative efficiencies, there is still significant degeneracy in terms of understanding the governing physics. I present several new results exploring the processes driving the Fundamental Plane over the black hole mass range. These include the first ever homogeneous fits of sources at approximately the same Eddington luminosity but millions of times different in mass, which I focus on for this proceeding article.

scholarly journals Eclipses of jets and discs of X-ray binaries as a powerful tool for understanding jet physics and binary parameters

2020 ◽  
Vol 499 (1) ◽  
pp. 957-973
Author(s):  
Thomas J Maccarone ◽  
Jakob van den Eijnden ◽  
Thomas D Russell ◽  
Nathalie Degenaar
Keyword(s):  
Jet Physics ◽  
Spectral Energy ◽  
Data Sets ◽  
Energy Distributions ◽  
X Ray ◽  
Orbital Parameters ◽  
Promising Target ◽  
Inclination Angles ◽  
Radio Band ◽  
X Ray Binaries

ABSTRACT We calculate the expected effects on the spectral energy distributions and light curves in X-ray binary jets from eclipses by the donor stars. Jets will be eclipsed for all inclination angles, with just the height along the jet where the eclipse takes place being set by the orbital parameters. Typically, eclipses will lead to 5–10 per cent reductions in the jet emission over a range of a factor of few in wavelength with a periodic modulation. In ideal systems with high inclination angles, relatively even mass ratios, and modest jet speeds, the eclipses may be deeper. We discuss how eclipses can be used to measure binary system parameters, as well as the height of the bases of the jets. We also discuss how, with data sets that will likely require future facilities, more detailed tests of models of jet physics could be made by establishing deviations from the standard recipes for compact conical flat spectrum jets and by determining the ingress and egress durations of the eclipses and measuring the transverse size of the jets. We provide representative calculations of expectations for different classes of systems, demonstrating that the most promising target for showing this effect in the radio band is the longer period ‘atoll’-class neutron star X-ray binaries, while in the optical and infrared bands, the best candidates are likely to be the most edge-on black hole X-ray binaries. We also discuss the effects of the outer accretion disc eclipsing the inner jet.

High Resolution X-Ray Spectroscopy at Jet

1988 ◽  
Vol 102 ◽  
pp. 283-291
Author(s):  
R. Giannella
Keyword(s):  
High Resolution ◽  
Rotation Velocity ◽  
Jet Physics ◽  
Main Task ◽  
Ion Temperature ◽  
Operational Parameters ◽  
X Ray ◽  
Operational Capabilities ◽  
The One ◽  
And Shifts

AbstractA high resolution X-ray crystal spectrometer was installed at JET in 1986. The main task of this instrument, designed and built by the ENEA Frascati Laboratory in collaboration with JET, is the measurement of the ion temperature and rotation velocity from Doppler broadenings and shifts. Stringent operation requirements considerably conditioned its versatility as a survey instrument or a tool for fundamental research. The unique conditions of the JET plasmas, however, allowed to observe in high resolution and identify lines from the highest ionization stages (B-like to H-like) of nickel in the vicinity of the resonance transitions of the one- and two-electron systems of this element. These spectra and their relevance to the study of JET physics are briefly presented. The comparison with atomic physics theoretical computations of He-like and H-like ions spectra observed at JET is also shortly presented. The most intense among these lines could regularly be monitored with adequate time resolution as to allow the production of an extensive data base. The experimental spectra are simulated by integrating the theoretical ones along the spectrograph line of sight across the plasma. Ion temperature as well as rotation velocity measurements in ohmic plasmas and additionally heated ones are discussed and their relationship with other physical quantities and operational parameters are shortly reviewed. Details of the spectrometer design, its lay-out on the JET site and its operational capabilities are also given.

scholarly journals Astrometric Observations of X-ray Binaries Using Very Long Baseline Interferometry

2014 ◽  
Vol 31 ◽  
Author(s):  
James C. A. Miller-Jones
Keyword(s):  
Proper Motion ◽  
Binary Systems ◽  
Very Long Baseline Interferometry ◽  
Jet Physics ◽  
Physical Parameters ◽  
X Ray ◽  
Long Baseline ◽  
Binary Evolution ◽  
Motion Studies

AbstractI review the astrophysical insights arising from high-precision astrometric observations of X-ray binary systems, focussing primarily (but not exclusively) on recent results with very long baseline interferometry. Accurate, model-independent distances from geometric parallax measurements can help determine physical parameters of the host binary system and constrain black hole spins via broadband X-ray spectral modelling. Long-term proper motion studies, combined with binary evolution calculations, can provide observational constraints on the formation mechanism of black holes. Finally, the astrometric residuals from parallax and proper motion fits can provide information on orbital sizes and jet physics. I end by discussing prospects for future progress in this field.

scholarly journals Formation, Equilibrium and Stability of Jets

1985 ◽  
Vol 107 ◽  
pp. 85-94
Author(s):  
Colin A. Norman
Keyword(s):  
Black Hole ◽  
Plasma Physics ◽  
Laval Nozzle ◽  
Magnetic Confinement ◽  
Mach Disk ◽  
Jet Physics ◽  
Particle Interactions ◽  
Jet Formation ◽  
X Ray ◽  
The Many

Consideration of the many observed types of jets on scales ranging from parsecs to megaparsecs seen in radio, optical, infrared and X-ray wavebands with a variety of morphologies both in galactic and extragalactic systems leads to some constraints on their fundamental nature. Jet formation is introduced with the concept of the Laval nozzle and related points include the problem of maintaining the nozzle, Mach disk effects due to under and over-expansion and the potential importance of magnetic confinement and focussing. Current ideas on jet formation at the black hole and accretion disk are given with emphasis on the plasma physics associated with black-hole electrodynamics, thermal and magnetically driven winds and thick disks. Stability of jet propagation is reviewed with emphasis on magnetised and unmagnetised Kelvin-Helmholtz instabilities and the various dominant modes. The particle acceleration physics of shocks, wave-particle interactions and turbulence is summarised while noting some outstanding plasma physics problems. Jet equilibrium associated with the non-linear saturation of instabilities, the formation of cocoons, shock stabilisation and magnetic fields is discussed. Detailed plasma physics studies that could significantly clarify jet physics are indicated.

scholarly journals Observational aspects of AGN jets at high energy

2014 ◽  
Vol 10 (S313) ◽  
pp. 1-11
Author(s):  
Jun Kataoka
Keyword(s):  
Large Scale ◽  
Gamma Ray ◽  
Galactic Center ◽  
Radio Galaxies ◽  
High Energy ◽  
Jet Physics ◽  
Space Telescopes ◽  
Energy Bands ◽  
X Ray ◽  
Astrophysical Jet

AbstractFor the last two decades, significant and dramatic progress has been made in understanding astrophysical jet sources, particularly in the X-ray and gamma-ray energy bands. For example, the Chandra X-ray observatory reveals a number of AGN jets extending from kpc to Mpc scales. More recently, the Fermi Gamma-ray Space Telescopes launched in 2008 started monitoring the gamma-ray sky with excellent sensitivity of about ten times greater than that of EGRET onboard CGRO, and has detected more than 2,000 sources (mostly AGNs) as of 2014. Moreover, Fermi-LAT has discovered gamma-ray emissions not only from blazars but from a dozen radio galaxies not previously known to emit gamma-rays. Closer to home, the Fermi-bubbles were discovered to extend 50 degrees above and below the Galactic center. These large scale diffuse gamma-ray structures are similar in structure to AGN lobes such as those seen in Cen A and provide evidence for past activity in our Galactic center. In this review, I will first summarize recent highlights of large scale jets in radio galaxies, specifically resolved by the Chandra X-ray observatory. Next I will move on to the gamma-ray sky to present some highlights from Fermi-LAT observations of “misaligned” blazars, namely radio galaxies. I will discuss a unification scheme connecting blazars and misaligned radio galaxies. In the last part, I will also briefly comment on recent multiband observations of the Fermi-bubble and possible impacts on the AGN jet physics in the near future.

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