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Black Holes and Relativistic Jets

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A special issue of Universe (ISSN 2218-1997). This special issue belongs to the section "Galaxies and Clusters".

Deadline for manuscript submissions: closed (30 September 2022) | Viewed by 20788

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Special Issue Editors

Dr. Ioana Dutan

E-Mail Website
Guest Editor

Institute of Space Science, RO-077125 Bucharest-Magurele, Romania
Interests: black holes; relativistic jets; particle-in-cell simulations

Dr. Nicholas R. MacDonald

E-Mail Website
Guest Editor

Max Planck Institute for Radio Astronomy, Bonn, Germany
Interests: 3D RMHD and PIC simulations of relativistic jets; polarized radiative transfer and ray-tracing techniques; global mm-VLBI; jet plasma composition

Special Issue Information

Dear Colleagues,

The connection between black holes and relativistic jets across all scales of black hole mass has long been supported by observational data. The aim of this Special Issue is to explore various aspects of the black hole-jet connection by bringing together recent results of developments on theoretical modeling, state-of-the-art numerical simulations, and high resolution observations. We welcome contributions on novel achievements in modeling accretion onto black holes, spin evolution of the black holes, certain aspects of jet physics (e.g., jet launching mechanisms, magnetic field configuration, acceleration, collimation, or non-thermal emission), and observational constrains on phenomena around supermasive black holes and X-ray binaries, including both the small and large scale jet structure.

Contents

Chapter 1. Jets from Super-Massive Black Holes

1.1 Jets on Kilo-Parsec Scales: Feedback & Interaction with The Galactic Environment

1.2 Jets on Sub-Parsec Scales: Peering into Blazars with Global and Space-Based millimeter-VLBI

1.3 Kinematic Evolution of Relativistic Plasmas: VLBI Monitoring of Relativistic Jets Across Two Decades

1.4 Jets as Fluids - Relativistic Magnetohydrodynamics (RMHD): Modeling the Macro-Physics of Relativistic Plasmas

1.5 Jets as Particles - Particle-in-Cell (PIC): Modeling the Micro-Physics of Relativistic Plasmas

1.6 Ray-Tracing & Radiative Transfer: Closing the Gap Between Simulations and Observations

1.7 Jet Formation and its Connection to the Black Hole and Accretion Disk

1.8 The Physics of Relativistic Jets Observed in Gamma-rays in the Fermi Era

1.9 Blazars in the Multi-Messenger Era: Relativistic Jets as Sources of High-Energy Neutrinos

1.10 A Multi-Year Project Observing and Modelling the Blazar OJ 287 from Radio to X-rays

1.11 The Origin of Matter at the Base of Relativistic Jets in Active Galactic Nuclei

1.12 Significance of Black Hole Visualization and Its Implication for Science Education Focusing on the Event Horizon Telescope Project

Chapter 2. Jets from Stellar-Mass Black Holes

2.1. Radio to X-ray Coupling in Black Hole X-ray Binaries

2.2. Superluminal Ejection from Black Holes in X-ray Binary Systems

Dr. Ioana Duţan
Dr. Nicholas R. MacDonald
Guest Editors

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Keywords

black holes
relativistic jets
accretion disk
active galactic nuclei
X-ray binaries

Published Papers (10 papers)

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Research

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20 pages, 2428 KiB

Open AccessArticle

Simulations on Synchrotron Radiation Intensity and Rotation Measure of Relativistic Magnetized Jet PKS 1502+106

by Che-Jui Chang and Jean-Fu Kiang

Universe 2023, 9(5), 235; https://doi.org/10.3390/universe9050235 - 17 May 2023

Viewed by 1014

Abstract

Strong γ-ray outbursts have been observed to emanate from PKS 1502+106, followed by highly variable fluxes in radio, visual, ultraviolet and X-ray bands. Numerical simulations have been conducted to relate the observations to potential theoretical models. The plasma attributes, such as mass density, plasma flow velocity and energy density, cannot be directly observed. However, the Stokes parameters of synchrotron radiation from the plasma can be measured to deduce the plasma attributes. Many studies have been conducted on synchrotron radiation intensity, with only a few on the rotation measure (RM) related to Faraday rotation. In this work, overpressured relativistic magnetized axisymmetric jets are simulated to acquire the synchrotron radiation maps, incorporating Faraday rotation, of the widely discussed jet, PKS 1502+106. The intensity maps and RM maps of the PKS 1502+106 are simulated under practical constraints, and compared with the available observation data to explore specific features of the jet. The simulated intensity maps match well with the observation data in size and shape. The observed spine–sheath polarization structure, sign change in the RM slice and opposite RM gradients have been reproduced. The conjecture of helical magnetic field morphology in the literature has also been validated by comparing the simulation results under different magnetic field morphologies. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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32 pages, 1377 KiB

Open AccessArticle

3C 120 Disk/Corona vs. Jet Variability in X-rays

by Elena Fedorova and Antonio Del Popolo

Universe 2023, 9(5), 212; https://doi.org/10.3390/universe9050212 - 28 Apr 2023

Cited by 1 | Viewed by 1309

Abstract

The 3C120 (Mrk 1506, UGC 03087, Mrk 9014) is a type 1 Seyfert (Sy1)/broad-line radio galaxy (BLRG) with intriguing variable jet activity featuring “dip” and “outburst” phases. Significant X-ray observational datasets have been collected for 3C120 by INTEGRAL, XMM-Newton, SWIFT, Suzaku, and other X-ray observational facilities. The overall X-ray spectrum of 3C 120 is too soft for typical radio-loud AGN, likely due to both variable spectral shape and jet contamination. Separating the “jet base” and nuclear (disc/corona) counterparts in the X-ray spectrum of 3C 120 can provide us with the possibility to investigate its variability in a more detailed way. Our objectives are to estimate separately the time variations of the accretion disc/corona and SSC/IC jet emission counterparts in the 3C 120 X-ray spectra and to analyze the physical state of the nucleus during different phases. Here, we attempt to use the connections between the synchrotron radio- and X-ray SSC/IC jet spectra and their photon indices and the dependence between the nuclear continuum and Fe-K iron luminescent line emission near 6.4 keV to separate the nuclear and jet base contributions to the total X-ray continuum. Using the X-ray observational dataset of 3C 120, we obtained separated fluxes that were interpreted as originating from the nucleus (disc/corona) and non-thermal SSC/IC jet base contributions. After this component separation, we identified the accretion disc/corona and jet states during different phases and compared them with the “jet/disk cycle” (Lohfink) and “magnetic plasmoid reconnection” (Shukla/Manheim) models. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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15 pages, 2632 KiB

Open AccessArticle

Detection of a Peculiar Drift in the Nuclear Radio Jet of the TeV Blazar Markarian 501

by Silke Britzen, Gopal Krishna, Emma Kun, Héctor Olivares, Ilya Pashchenko, Frédéric Jaron, Josefa Becerra González and David Paneque

Universe 2023, 9(3), 115; https://doi.org/10.3390/universe9030115 - 23 Feb 2023

Cited by 3 | Viewed by 995

Abstract

Mrk 501 is one of the most prominent TeV-emitting blazars and belongs to the class of high synchrotron peaked (HSP) blazars. The Doppler factors derived from the jet kinematics are much too low to provide sufficient beaming for the detected high-energy emission (the [...] Read more.

^{\circ}

difference in orientation between the inner parsec-scale jet and the kpc-scale jet structure. We have performed a detailed analysis of the pc-scale jet kinematics, based on 23 years of VLBA observations (at 15 GHz) and find, in addition to robustly consolidating the already claimed stationary jet features and a hinted absence of component ejections, a significant drift of the outer nuclear jet. The two outermost jet features move with somewhat higher but still subluminal speeds. Albeit, they move orthogonally to the inner jet, which itself does not partake in the drifting motion. The effect of this intriguing kinematics is that the jet appears strongly curved at first (1995) but then appears to straighten out (2018). To our knowledge, this is the first time that the orthogonal swing of just the outer part of a nuclear jet has been observed. We discuss the possible physical nature of this turning maneuver. In addition, we report evidence for jet emission, which most likely originates in a spine–sheath structure. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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10 pages, 1750 KiB

Open AccessArticle

Linear Polarization Signatures of Particle Acceleration in High-Synchrotron-Peak Blazars

by Alan P. Marscher and Svetlana G. Jorstad

Universe 2022, 8(12), 644; https://doi.org/10.3390/universe8120644 - 04 Dec 2022

Cited by 7 | Viewed by 1350

Abstract

Blazars whose synchrotron spectral energy distribution (SED) peaks at X-ray energies need to accelerate electrons to energies in the >100 GeV range in relativistic plasma jets at distances of parsecs from the central engine. Compton scattering by the same electrons can explain high luminosities at very high photon energies (>100 GeV) from the same objects. Turbulence combined with a standing conical shock can accomplish this. Such a scenario can also qualitatively explain the level and variability of linear polarization observed at optical frequencies in these objects. Multi-wavelength polarization measurements, including those at X-ray energies by the Imaging X-ray Polarimetry Explorer (IXPE), find that the degree of polarization is several times higher at X-ray than at optical wavelengths, in general agreement with the turbulence-plus-shock picture. Some detailed properties of the observed polarization can be naturally explained by this scenario, while others pose challenges that may require modifications to the model. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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222 pages, 2537 KiB

Open AccessEditor’s ChoiceArticle

A New Sample of Gamma-Ray Emitting Jetted Active Galactic Nuclei

by Luigi Foschini, Matthew L. Lister, Heinz Andernach, Stefano Ciroi, Paola Marziani, Sonia Antón, Marco Berton, Elena Dalla Bontà, Emilia Järvelä, Maria J. M. Marchã, Patrizia Romano, Merja Tornikoski, Stefano Vercellone and Amelia Vietri

Universe 2022, 8(11), 587; https://doi.org/10.3390/universe8110587 - 04 Nov 2022

Cited by 18 | Viewed by 3029

Abstract

We considered the fourth catalog of gamma-ray point sources produced by the Fermi Large Area Telescope (LAT) and selected only jetted active galactic nuclei (AGN) or sources with no specific classification, but with a low-frequency counterpart. Our final list is composed of 2980 gamma-ray point sources. We then searched for optical spectra in all the available literature and publicly available databases, to measure redshifts and to confirm or change the original LAT classification. Our final list of gamma-ray emitting jetted AGN is composed of BL Lac Objects (40%), flat-spectrum radio quasars (23%), misaligned AGN (2.8%), narrow-line Seyfert 1, Seyfert, and low-ionization nuclear emission-line region galaxies (1.9%). We also found a significant number of objects changing from one type to another, and vice versa (changing-look AGN, 1.1%). About 30% of gamma-ray sources still have an ambiguous classification or lack one altogether. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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21 pages, 4555 KiB

Open AccessArticle

Exploring the Fundamental Mechanism in Driving Highest-Velocity Ionized Outflows in Radio AGNs

by Ashraf Ayubinia, Yongquan Xue, Jong-Hak Woo, Huynh Anh Nguyen Le, Zhicheng He, Halime Miraghaei and Xiaozhi Lin

Universe 2022, 8(11), 559; https://doi.org/10.3390/universe8110559 - 26 Oct 2022

Cited by 3 | Viewed by 1123

Abstract

We investigate the ionized gas kinematics relationship with X-ray, radio and accreting properties using a sample of 348 nearby (

z < 0.4

) SDSS-FIRST-X-ray detected AGNs. X-ray properties of our sample are obtained from XMM-Newton, Swift and Chandra observations. We unveil [...] Read more.

We investigate the ionized gas kinematics relationship with X-ray, radio and accreting properties using a sample of 348 nearby (

z < 0.4

) SDSS-FIRST-X-ray detected AGNs. X-ray properties of our sample are obtained from XMM-Newton, Swift and Chandra observations. We unveil the ionized gas outflows in our sample manifested by the non-gravitational broad component in [O iii]λ5007Å emission line profiles. From the comparison of the correlation of non-parametric outflow velocities (i.e., the velocity width, the maximal velocity of outflow and line dispersion) with X-ray luminosity and radio luminosity, we find that outflow velocities have similarly positive correlations with both X-ray and radio luminosity. After correcting for the gravitational component, we find that the [O iii] velocity dispersion normalized by stellar mass also increases with both X-ray luminosity and radio luminosity. We also find that, for a given X-ray (radio) luminosity, radio (X-ray) luminous AGNs have higher outflow velocities than non-radio (non-X-ray) luminous AGNs. Therefore, we find no clear preference between X-ray luminosity and radio luminosity in driving high-velocity ionized outflows and conclude that both AGN activity and small-scale jets contribute comparably. Moreover, there is no evidence that our obscured AGNs are preferentially associated with higher velocity outflows. Finally, we find a turning point around log

(λ_{E d d}) ≃ - 1.3

when we explore the dependency of outflow velocity on Eddington ratio. It can be interpreted considering the role of high radiation pressure (log

(λ_{E d d}) ≳ - 1.3

) in causing drastic reduction in the covering factor of the circumnuclear materials. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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10 pages, 729 KiB

Open AccessArticle

Constraints on a Tidal Charge of the Supermassive Black Hole in M87* with the EHT Observations in April 2017

by Alexander F. Zakharov

Universe 2022, 8(3), 141; https://doi.org/10.3390/universe8030141 - 22 Feb 2022

Cited by 25 | Viewed by 1730

Abstract

More than two years ago the Event Horizon Telescope collaboration presented the first image reconstruction around the shadow for the supermassive black hole in M87*. It gives an opportunity to evaluate the shadow size. Recently, the Event Horizon Telescope collaboration constrained parameters (“charges”) of spherical symmetrical metrics of black holes from an estimated allowed interval for shadow radius from observations of M87* in 2017. Earlier, analytical expressions for the shadow radius as a function of charge (including a tidal one) in the case of Reissner–Nordström metric have been obtained. Some time ago, Bin-Nun proposed to apply a Reissner–Nordström metric with a tidal charge as an alternative to the Schwarzschild metric in Sgr A*. If we assume that a Reissner–Nordström black hole with a tidal charge exists in M87*, therefore, based on results of the shadow size evaluation for M87* done by the Event Horizon Telescope collaboration we constrain a tidal charge. Similarly, we evaluate a tidal charge from shadow size estimates for Sgr A*. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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23 pages, 1833 KiB

Open AccessArticle

The Origin of Matter at the Base of Relativistic Jets in Active Galactic Nuclei

by Gustavo E. Romero and Eduardo Gutiérrez

Universe 2020, 6(7), 99; https://doi.org/10.3390/universe6070099 - 18 Jul 2020

Cited by 11 | Viewed by 3395

Abstract

The generation of relativistic jets in active sources such as blazars is a complex problem with many aspects, most of them still not fully understood. Relativistic jets are likely produced by the accretion of matter and magnetic fields onto spinning black holes. Ergospheric dragging effects launch a Poynting-dominated outflow in the polar directions of these systems. Observations with very high resolution of the jet in the nearby radio galaxy M87 and evidence of extremely fast variability in the non-thermal radiation of several other objects indicate that charged particles produce synchrotron emission and gamma rays very close to the base of the jet. How these particles are injected into the magnetically shielded outflow is a mystery. Here we explore the effects of various processes in the hot accretion inflow close to the black hole that might result in the copious production of neutral particles which, through annihilation and decay in the jet’s funnel, might load the outflow with mass and charged particles on scales of a few Schwarzschild radii. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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13 pages, 2003 KiB

Open AccessArticle

Significance of Black Hole Visualization and Its Implication for Science Education Focusing on the Event Horizon Telescope Project

by Hye-Gyoung Yoon, Jeongwoo Park and Insun Lee

Universe 2020, 6(5), 70; https://doi.org/10.3390/universe6050070 - 25 May 2020

Cited by 1 | Viewed by 3075

Abstract

In recent years, substantial progress has been made in black hole visualization. However, there is a lack of essential up-to-date information regarding black holes in current school curricula, in spite of students’ substantial interest in black holes. In this study, we examined the implications of the Event Horizon Telescope project, a recent achievement of the scientific community, for science education. An analysis of the black hole visualization research process, based on Giere’s scientific reasoning model, revealed that there are two categories of the black hole visualization processes: visualization through prediction based on a theory and visualization through real-world observation data. Black hole images are not merely scientific outputs that students must memorize; rather, they can be a useful resource for learning the nature of science and the characteristics of scientific reasoning. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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Review

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26 pages, 6180 KiB

Open AccessReview

Active Galactic Nuclei as Potential Sources of Ultra-High Energy Cosmic Rays

by Frank M. Rieger

Universe 2022, 8(11), 607; https://doi.org/10.3390/universe8110607 - 17 Nov 2022

Cited by 9 | Viewed by 1935

Abstract

Active Galactic Nuclei (AGNs) and their relativistic jets belong to the most promising class of ultra-high-energy cosmic ray (UHECR) accelerators. This compact review summarises basic experimental findings by recent instruments, and discusses possible interpretations and astrophysical constraints on source energetics. Particular attention is given to potential sites and mechanisms of UHECR acceleration in AGNs, including gap-type particle acceleration close to the black hole, as well as first-order Fermi acceleration at trans-relativistic shocks and stochastic shear particle acceleration in large-scale jets. It is argued that the last two represent the most promising mechanisms given our current understanding, and that nearby FR I type radio galaxies provide a suitable environment for UHECR acceleration. Full article

(This article belongs to the Special Issue Black Holes and Relativistic Jets)

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