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Related papers: Imaging on PAPER: Centaurus A at 148 MHz

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We study the particle energy distribution in the cocoon surrounding Cygnus A, using radio images between 151 MHz and 15 GHz and a 200 ks Chandra ACIS-I image. We show that the excess low frequency emission in the the lobe further from Earth…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 K. C. Steenbrugge , I. Heywood , K. M. Blundell

High angular resolution radio continuum images of NGC 1976 (M42, Orion A) at frequency=330 MHz (wavelength=91 cm), 1.5 GHz (20 cm) and 10.6 GHz (2.8 cm), have been aligned, placed on a common grid, smoothed to common resolutions of 80"…

Space Physics · Physics 2015-05-30 T. L. Wilson , S. Casassus , Katie M. Chynoweth

The origin of the 3.55 keV excess reported in various galaxies and galaxy clusters remains unknown. Non-observations of the line in dwarf spheroidal galaxies (dSphs) create tension with galaxy cluster observations when considering a direct…

High Energy Astrophysical Phenomena · Physics 2017-12-04 Nicholas Jennings

Aims. The aim of this work is to further investigate the nature of PAH excitation and emission especially in the context of tracing star formation in a variety of extragalactic environments. Here we turn our attention to the energetic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 L. E. Tacconi-Garman , E. Sturm

Long-term measurements of the radio flux density of Cassiopeia A relative to Cygnus A have been carried out at 927 and 151.5 MHz. It was found the following mean secular decrease rates of the radio emission of Cassiopeia A: $(0.72\pm 0.03)%…

Astrophysics · Physics 2007-05-23 E. N. Vinyajkin , V. A. Razin

The extended lobes of radio galaxies are examined as sources of X-ray and gamma-ray emission via inverse Compton scattering of 3K background photons. The Compton spectra of two exemplary examples, Fornax A and Centaurus A, are estimated…

Astrophysics · Physics 2009-06-23 C. C. Cheung

We present the first clear detection of ionized Fe-K emission and absorption components in the nearby radio galaxy Centaurus A, revealed by the high-resolution XRISM/Resolve detector. In the 6.5-6.9 keV band, XRISM reveals multiple Fe XXV…

Centaurus A is the closest active galactic nucleus. High resolution imaging using Very Long Baseline Interferometry (VLBI) enables us to study the spectral and kinematic behavior of the radio jet-counterjet system on sub-parsec scales,…

This paper focuses on two aspects of the Physics of Radio Galaxies in which it has been proposed that relativistic beaming of radiation is necessary to account for the observations. Physical arguments are presented which show that it is…

Astrophysics · Physics 2007-05-23 Geoffrey V. Bicknell

We present J, H and K-band images and 0.9-2.5 micron spectra of the nuclear regions of Centaurus A obtained with IRIS on the AAT. While K band has a point source coincident with the nucleus, at H and J we identify diffuse structure…

Astrophysics · Physics 2009-10-31 J. J. Bryant , R. W. Hunstead

We report X-ray observations of the nearby, powerful radio galaxy Pictor A with the Chandra Observatory and optical and near uv observations of its western radio hot spot with the Hubble Space Telescope. X-ray emission is detected from the…

Astrophysics · Physics 2009-10-31 A. S. Wilson , A. J. Young , P. L. Shopbell

A new epoch of VLA measurements of Kepler's supernova remnant was obtained to make accurate measurements of the radio spectral index variations and polarization. We have compared these new radio images with Halpha, infrared, and X-ray data…

Astrophysics · Physics 2009-11-07 Tracey DeLaney , Barron Koralesky , Lawrence Rudnick , John R. Dickel

The XMM-Newton satellite has revealed extended X-ray emission from the eastern radio lobe of the Fanaroff-Riley II Radio Galaxy Pictor A. The X-ray spectrum, accumulated on a region covering about half the entire radio lobe, is well…

We present high resolution images of the 12CO(2-1) emission in the central 1' (1 kpc) of NGC 5128 (Centaurus A), observed using the SMA. We elucidate for the first time the distribution and kinematics of the molecular gas in this region…

Astrophysics of Galaxies · Physics 2011-02-11 D. Espada , S. Matsushita , A. Peck , C. Henkel , D. Iono , F. P. Israel , S. Muller , G. Petitpas , Y. Pihlstroem , G. B. Taylor , Dinh-V-Trung

We present preliminary results from two observations of the radio galaxy Centaurus A performed by the BeppoSAX satellite. We did not detect any spectral variation of the nuclear continuum in spite of the long-term flux change (by a factor…

Astrophysics · Physics 2009-10-31 P. Grandi , C. M. Urry , L. Maraschi

The Pierre Auger Observatory has associated a few ultra high energy cosmic rays with the direction of Centaurus A. This source has been deeply studied in radio, infrared, X-ray and $\gamma$-rays (MeV-TeV) because it is the nearest…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Nissim fraija , M. M. Gonzalez , M. Perez , A. Marinelli

We report the discovery of faint very high energy (VHE, E>100 GeV) gamma-ray emission from the radio galaxy Centaurus A in observations performed with the H.E.S.S. experiment, an imaging atmospheric Cherenkov telescope array consisting of…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-17 HESS Collaboration , F. Aharonian

We report the discovery of a statistically significant hardening in the Fermi-LAT $\gamma$-ray spectrum of Centaurus A's core, with the spectral index hardening from $\Gamma_{1}=2.73 \pm 0.02$ to $\Gamma_{1}=2.29 \pm 0.07$ at a break energy…

High Energy Astrophysical Phenomena · Physics 2017-11-16 Anthony M. Brown , Celine Bœhm , Jamie Graham , Thomas Lacroix , Paula Chadwick , Joe Silk

Deep Chandra and VLA imaging reveals a clear correlation between X-ray and radio emission on scales $\sim 100$~kpc in the Spiderweb radio galaxy at z=2.16. The X-ray emission associated with the extended radio source is likely dominated by…

We combine results from ROSAT, Chandra, and multifrequency VLBA observations of the Compact Steep Spectrum quasar 3C 48. We infer that the X-ray spectrum of the nucleus is made up of a soft, variable, steep-spectrum component, and harder,…

Astrophysics · Physics 2009-11-10 D. M. Worrall , M. J. Hardcastle , T. J. Pearson , A. C. S. Readhead
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