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Related papers: Recurrent Activity in Active Galactic Nuclei

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Variability of active galactic nuclei (AGNs) has long been servicing as an essential avenue of exploring the accretion physics of black hole (BH). There are two commonly used methods for analyzing AGN variability. First, the AGN…

Astrophysics of Galaxies · Physics 2024-07-04 Zhen-Bo Su , Zhen-Yi Cai , Mouyuan Sun , Hengxiao Guo , Wei-Min Gu , Jun-Xian Wang

Energetic feedback from active galactic nuclei (AGN) is an important ingredient for regulating the star-formation history of galaxies in models of galaxy formation, which makes it important to study how AGN feedback actually occurs in…

Radio mode feedback, in which most of the energy of an active galactic nucleus (AGN) is released in a kinetic form via radio-emitting jets, is thought to play an important role in the maintenance of massive galaxies in the present-day…

Astrophysics of Galaxies · Physics 2015-06-22 W. Ishibashi , M. W. Auger , D. Zhang , A. C. Fabian

Steep spectrum radio sources associated with active galactic nuclei (AGN) may contain remnants of past AGN activity episodes. Novel instruments like the LOw Frequency ARray (LOFAR) are enabling studies of these fascinating structures to be…

Most Active Galactic Nuclei (AGN) are Radio Quiet, with radio emission that may arise from star-formation activity, AGN-driven winds, weak jets, and coronal activity. Disentangling these mechanisms is challenging and requires detailed…

Galaxy clusters grow by a sequence of mergers with other clusters and galaxy groups. During these mergers, shocks and/or turbulence are created within the intracluster medium (ICM). In this process, particles could be accelerated to highly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 R. J. van Weeren , H. J. A. Rottgering , M. Bruggen

Context: Active Galactic Nuclei are highly variable emitters of electromagnetic waves from the radio to the gamma-ray regime. This variability may be periodic, which in turn could be the signature of a binary black hole. Systems of black…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Constanze Roedig , Thomas Burkart , Oliver Elbracht , Felix Spanier

Feedback from radio jets associated with Active Galactic Nuclei (AGN) plays a profound role in the evolution of galaxies. Kinetic power of these radio jets appears to show temporal variation, but the mechanism(s) responsible for this…

Continuum and emission-line variability of active galactic nuclei provides a powerful probe of microarcsecond scale structures in the central regions of these sources. In this contribution, we review basic concepts and methodologies used in…

Astrophysics · Physics 2016-11-03 Bradley M. Peterson

Analysis of the frequency and physical properties of galaxies with star-formation and AGN activity in different environments in the local universe is a cornerstone for understanding structure formation and galaxy evolution. We have built a…

Astrophysics · Physics 2008-11-26 Pietro Reviglio , David J. Helfand

We investigate radio-mode AGN activity among post-starburst galaxies from the Sloan Digital Sky Survey to determine whether AGN feedback may be responsible for the cessation of star formation. Based on radio morphology and radio-loudness…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Min-Su Shin , Michael A. Strauss , Rita Tojeiro

We investigate how the total radio luminosity of AGN-powered radio sources depends on their accretion luminosity and the central black hole mass. We find that AGNs form two distinct and well separated sequences on the radio-loudness -…

Astrophysics · Physics 2007-07-17 L. Stawarz , M. Sikora , J. -P. Lasota

Restarted radio galaxies represent a unique tool to investigate the duty cycle of the jet activity in Active Galactic Nuclei. Due to a sharp discontinuity of the GHz spectral index distribution within its lobes, the radio galaxy 3C388 has…

Compact radio cores in radio-loud active galactic nuclei (AGNs) are classical targets of Very-Long-Baseline interferometric (VLBI) research. Until today little has been known about their X-ray properties in comparison to radio-quiet AGNs.…

Astrophysics · Physics 2007-05-23 M. Kadler , E. Ros , J. Kerp , Y. Y. Kovalev , J. A. Zensus

The cores of active galactic nuclei (AGN) harbor some of the most extreme conditions of matter and energy in the Universe. One of the major goals of high-energy astrophysics is to probe these extreme environments in the vicinity of…

Astrophysics · Physics 2009-10-31 K. A. Weaver

Some giant radio galaxies selected at X-rays with an AGN show signs of a restarted nuclear activity. One object in this peculiar class is Mrk1498, a giant low-frequency double radio source that shows extended emission in [OIII]. This…

Astrophysics of Galaxies · Physics 2024-09-13 S. Cazzoli , L. Hernández-García , I. Márquez , J. Masegosa , G. Bruni , F. Panessa , L. Bassani

Recent works show that the radio power of quasars accreting at very high rates can reach surprisingly high values. These studies suggest that this radio emission might originate from star formation, but lack of data leaves open the…

Active galactic nucleus (AGN) powered jets can accelerate cosmic ray electrons, leading to the observed radio synchrotron emission. To simulate this emission, jet dynamics in galaxy clusters must be coupled to electron spectral modelling.…

Astrophysics of Galaxies · Physics 2026-01-19 Léna Jlassi , Rainer Weinberger , Christoph Pfrommer , Maria Werhahn , Joseph Whittingham , Philipp Girichidis

The active galactic nucleus (AGN) phenomena results from a supermassive black hole accreting its surrounding gaseous and dusty material. The infrared (IR) regime provides most of the information to characterize the dusty structures that…

Astrophysics of Galaxies · Physics 2022-05-31 Jianwei Lyu , George Rieke

A recent study of the X-ray source XMMUJ134736.6+173403 has revealed a strong quasi-periodic modulation of the X-ray flux. The observation of two quasiperiodic oscillations (QPOs) that occur on a daily timescale and exhibit a 3:1 frequency…

High Energy Astrophysical Phenomena · Physics 2019-02-06 Kateřina Goluchová , Gabriel Török , Eva Šrámková , Marek A. Abramowicz , Zdeněk Stuchlík , Jiří Horák
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