English
Related papers

Related papers: Probing accretion activity in radio sources using …

200 papers

We present deep Spitzer/IRS spectra for complete samples of 46 2Jy radio galaxies (0.05<z<0.7) and 19 3CRR FRII radio galaxies (z<0.1), and use the detection of polycyclic aromatic hydrocarbon (PAH) features to examine the incidence of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 D. Dicken , C. Tadhunter , D. Axon , R. Morganti , A. Robinson , M. B. N. Kouwenhoven , H. Spoon , P. Kharb , K. J. Inskip , J. Holt , C. Ramos Almeida , N. P. H. Nesvadba

We present results from a comprehensive imaging survey of 70 radio galaxies at redshifts 1<z<5.2 using all three cameras onboard the Spitzer Space Telescope. The resulting spectral energy distributions unambiguously show a stellar…

We present 1.1 mm observations for a sample of 16 powerful radio galaxies at 0.5<z<5.2 and a radio quiet quasar at z=6.3, obtained using the AzTEC bolometer array mounted on the ASTE or the JCMT. This paper more than doubles the number of…

We report 20 and 6 cm VLA deep observations of the CDF-S including the Extended CDF-S. We discuss the radio properties of 266 cataloged radio sources, of which 198 are above a 20 cm completeness level reaching down to 43 microJy at the…

Astrophysics · Physics 2009-11-13 K. I. Kellermann , E. B. Fomalont , V. Mainieri , P. Padovani , P. Rosati , P. Shaver , P. Tozzi , N. Miller

Axion-like particles, which we call axions, can compose the missing dark matter and may form substructures such as miniclusters and axion stars. We obtain the mass distributions of axion stars derived from their host miniclusters in our…

High Energy Physics - Phenomenology · Physics 2024-09-23 Dennis Maseizik , Sagnik Mondal , Hyeonseok Seong , Günter Sigl

Radio observations allow us to identify a wide range of active galactic nuclei (AGN), which are galaxies that have gas accreting onto the supermassive black-hole at the centre. By observing these sources at multiple radio frequencies, a…

Astrophysics of Galaxies · Physics 2023-07-19 Sarah V. White

We are using the Australia Telescope Compact Array to image about six square degrees surrounding the Chandra Deep Field South and European Large Area ISO Survey - South 1 regions, with the aim of producing the widest deep radio survey ever…

Astrophysics · Physics 2007-05-23 Ray P. Norris , Enno Middelberg , Brian J. Boyle

We investigate the possible contribution from the emission of accretion flows around supermassive black holes in early type galaxies to current measurements of the Cosmic Microwave Background (CMB) at radio frequencies. We consider a range…

Astrophysics · Physics 2009-11-10 Elena Pierpaoli , Rosalba Perna

Nearby blue compact dwarf (BCD) galaxies are arguably our best local analogues of galaxies in the earlier Universe that may host relics of black hole (BH) seeds. Here we present high-resolution Chandra X-ray Observatory and Karl G. Jansky…

Astrophysics of Galaxies · Physics 2022-06-24 Lilikoi J. Latimer , Amy E. Reines , Richard M. Plotkin , Thomas D. Russell , James J. Condon

Using mid-infrared and radio selection criteria, we pre-select a sample of candidate high-redshift type-2 quasars in the Subaru XMM-Newton Deep Field (SXDF). To filter out starburst contaminants, we use a bayesian method to fit the spectral…

We present a comprehensive analysis of Chandra X-ray observations of 15 young radio quasars at redshifts $4.5 < z < 5.0$. All sources are detected in the $0.5-7.0$ keV energy band. Emission spectra are extracted, and the average photon…

Our MAMBO 1.2 mm blank field imaging survey of ~0.75 sqd has uncovered four unusually bright sources, with flux densities between 10 and 90 mJy, all located in the Abell 2125 field. The three brightest are flat spectrum radio sources with…

We report on the identifications of radio sources from our survey of the Hubble Deep Field and the SSA13 fields, both of which comprise the deepest radio surveys to date at 1.4 GHz and 8.5 GHz respectively. About 80% of the microjansky…

Submillimeter (and in some cases millimeter) wavelength continuum measurements are presented for a sample of 40 active galactic nuclei (probably all quasars) lensed by foreground galaxies. The object of this study is to use the lensing…

Astrophysics · Physics 2009-11-07 Richard Barvainis , Rob Ivison

We report the result of optical identifications of FIRST radio sources with the Hyper Suprime-Cam Subaru Strategic Program survey (HSC-SSP). The positional cross-match within 1" between the FIRST and HSC-SSP catalogs (i ~< 26) produced more…

We present millimeter and radio observations of 13 SDSS quasars at reshifts z~6. We observed eleven of them with the Max-Planck Millimeter Bolometer Array (MAMBO-2) at the IRAM 30m-telescope at 250 GHz and all of them with the Very Large…

We discuss identifications for 18 sources from our MAMBO 1.2mm survey of the region surrounding the NTT Deep Field. We have obtained accurate positions from Very Large Array 1.4GHz interferometry and in a few cases IRAM mm interferometry,…

Astrophysics · Physics 2009-11-10 H. Dannerbauer , M. D. Lehnert , D. Lutz , L. Tacconi , F. Bertoldi , C. Carilli , R. Genzel , K. M. Menten

The emission of continuous gravitational waves (CWs) possibly explains why pulsars spinning with a period shorter than a millisecond have not been observed so far. Neutron stars accreting mass at the highest rates are the most promising…

Despite the plethora of deep (sub-mJy) radio surveys there remains considerable doubt as to the exact nature of the galaxies contributing to the source counts. Current evidence suggests that starformation in moderately luminous 'normal'…

Astrophysics · Physics 2009-11-11 Nick Seymour , Derek Moss , Ian McHardy , Katherine Gunn , Mat Page , Nic Loaring , Tom Dwelly

Infrared-Faint Radio Sources (IFRSs) are a class of radio objects found in the Australia Telescope Large Area Survey (ATLAS) which have no observable mid-infrared counterpart in the Spitzer Wide-area Infrared Extragalactic (SWIRE) survey.…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-30 M. T. Huynh , R. P. Norris , B. Siana , E. Middelberg