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The radiative and jet power in active galactic nuclei is generated by accretion of material on to supermassive galactic-centre black holes. For quasars, where the radiative power is by definition very high, objects with high radio…

Astrophysics of Galaxies · Physics 2021-12-28 Gülay Gürkan , Judith Croston , Martin Hardcastle , Vijay Mahatma , Beatriz Mingo , Wendy Williams

We present the first results from the Quasar Feedback Survey, a sample of 42 z<0.2, [O III] luminous AGN (L[O III]>10^42.1 ergs/s) with moderate radio luminosities (i.e. L(1.4GHz)>10^23.4 W/Hz; median L(1.4GHz)=5.9x10^23 W/Hz). Using high…

We report results from a spectral and timing analysis of M82 X-1, one of the brightest known ultraluminous X-ray sources. Data from a new 105 ks {\it XMM-Newton} observation of M82 X-1, performed in April 2004, and of archival {\it…

Astrophysics · Physics 2009-11-13 P. Mucciarelli , P. Casella , T. Belloni , L. Zampieri , P. Ranalli

Thermal mid-infrared emission of quasars requires an obscuring structure that can be modeled as a magneto-hydrodynamic wind in which radiation pressure on dust shapes the outflow. We have taken the dusty wind models presented by Keating and…

Astrophysics of Galaxies · Physics 2015-05-19 S. C. Gallagher , J. E. Everett , M. M. Abado , S. K. Keating

We describe the selection of candidate radio-loud quasars obtained by cross-matching radio source positions from the low-frequency (151 MHz) 7C survey with optical positions from five pairs of EO POSS-I plates scanned with the Cambridge…

Hard, non-thermal, persistent pulsed X-ray emission extending between 10 keV and $\sim 150$ keV has been observed in nearly ten magnetars. For inner-magnetospheric models of such emission, resonant inverse Compton scattering of soft thermal…

High Energy Astrophysical Phenomena · Physics 2018-02-28 Zorawar Wadiasingh , Matthew G. Baring , Peter L. Gonthier , Alice K. Harding

Magnetic fields are expected to permeate the circumgalactic medium (CGM) of galaxies, yet direct constraints at high redshift remain limited by the lack of high-quality Faraday rotation measure (RM) data. Using the RMs from SPICE-RACS DR2…

We report on the search for distant radio-loud quasars in the Cosmic Lens All Sky Survey (CLASS) of flat spectrum radio sources with S_5GHz>30 mJy. Unresolved optical counterparts were selected from APM scans of POSS-I plates, with e<19.0…

The goal of this work is to investigate the Faraday rotation measure (RM) of radio galaxies in hot galaxy clusters in order to establish a possible connection between the magnetic field strength and the gas temperature of the intracluster…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 F. Govoni , K. Dolag , M. Murgia , L. Feretti , S. Schindler , G. Giovannini , W. Boschin , V. Vacca , A. Bonafede

We analyze the optical properties of Radio-Loud quasars along the Main Sequence (MS) of quasars. A sample of 355 quasars selected on the basis of radio detection was obtained by cross-matching the FIRST survey at 20cm and the SDSS DR12…

Astrophysics of Galaxies · Physics 2021-07-14 A. del Olmo , P. Marziani , V. Ganci , M. D'Onofrio , E. Bon , N. Bon , A. C. Negrete

We present results for the (color)magnetic and (color)electric screening masses of the Quark-Gluon Plasma in the presence of an external magnetic field. The screening masses are extracted from the correlators of Polyakov loops, determined…

High Energy Physics - Lattice · Physics 2017-04-28 Claudio Bonati , Massimo D'Elia , Marco Mariti , Michele Mesiti , Francesco Negro , Andrea Rucci , Francesco Sanfilippo

The regular monitoring of flat-spectrum radio quasars (FSRQs) in $\gamma$-rays by Fermi-LAT since past 12 years indicated six sources who exhibited extreme $\gamma$-ray outbursts crossing daily flux of $10^{-5}$ photons/cm$^{2}$/s. We…

High Energy Astrophysical Phenomena · Physics 2021-04-20 Abhradeep Roy , Sonal R. Patel , Arkadipta Sarkar , Anshu Chatterjee , Varsha R. Chitnis

In a companion paper, we reported the self-consistent formation of quasar accretion disks with inflow rates $\sim 10\,{\rm M_{\odot}\,yr^{-1}}$ down to <300 Schwarzschild radii from cosmological…

We present the measurements of Faraday rotation for 477 pulsars observed by the Parkes 64-m radio telescope and the Green Bank 100-m radio telescope. Using these results along with previous measurements for pulsars and extra-galactic…

Astrophysics of Galaxies · Physics 2018-01-31 J. L. Han , R. N. Manchester , W. van Straten , P. Demorest

Active Galactic Nuclei (AGN) are some of the most luminous and extreme environments in the Universe. The central engines of AGN, believed to be super-massive black-holes, are fed by accretion discs threaded by magnetic fields within a dense…

Quasisymmetry is an unusual symmetry that can be present in toroidal magnetic fields, enabling confinement of charged particles and plasma. Here it is shown that both quasi-axisymmetry and quasi-helical symmetry can be achieved to a much…

Plasma Physics · Physics 2022-02-02 Matt Landreman , Elizabeth Paul

Results are presented of a new VLA-ROSAT study that probes the magnetic field strength and distribution over a sample of 16 ``normal'' low redshift (z < 0.1) galaxy clusters. The clusters span two orders of magnitude in X-ray luminosity,…

Astrophysics · Physics 2009-10-31 T. E. Clarke , P. P. Kronberg , H. Boehringer

Central supermassive black holes of active galactic nuclei host hot plasma with a temperature of $10^9$ K, namely coronae. Like the Sun, black hole coronae are theoretically believed to be heated by their magnetic activity, which have never…

High Energy Astrophysical Phenomena · Physics 2018-12-26 Yoshiyuki Inoue , Akihiro Doi

The remarkable rapid variations in radio flux density and polarization of the quasar PKS 0405-385 observed in 1996 are subject to a correlation analysis, from which characteristic time scales and amplitudes are derived. The variations are…

Astrophysics · Physics 2009-11-07 Barney J. Rickett , Lucyna Kedziora-Chudczer , David L. Jauncey

We present detailed imaging of Faraday rotation and depolarization for the radio galaxies 0206+35, 3C 270, 3C 353 and M 84, based on Very Large Array observations at multiple frequencies in the range 1365 to 8440 MHz. This work suggests a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 D. Guidetti , R. A. Laing , A. H. Bridle , P. Parma , L. Gregorini