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Radio continuum observations of new radio halos and relics from the NVSS and WENSS surveys
Radio Continuum: galaxies – Galaxies: Clusters: general, intracluster medium – Cosmology: large-scale structure of Universe
2011/10/20
Radio halos and relics are diffuse radio sources found in galaxy clusters showing significant substructure at X-ray wavelengths. These sources provide important information about non-thermal processes...
Evolution in the clustering strength of radio galaxies
galaxies active Galaxies galaxies evolution Galaxies
2011/10/20
We cross match the NVSS and FIRST surveys with three large photometric catalogues of luminous red galaxies (LRGs) to define radio-loud samples. These have median redshifts 0.35, 0.55 and 0.68 and, by ...
Understanding Giant Radio Galaxy J1420-0545: Large-Scale Morphology, Environment, and Energetics
Understanding Giant Radio Galaxy J1420-0545: Large-Scale Morphology, Environment, and Energetics
2011/10/18
In this paper we consider the possibility that the structure of the largest radio galaxy J1420-0545 is formed by a restarted rather than a primary jet activity. This hypothesis is motivated by the unu...
From the Blazar Sequence to the Blazar Envelope: Revisiting the Relativistic Jet Dichotomy in Radio-loud AGN
Blazar Envelope Revisiting Relativistic Jet Dichotomy Radio-loud AGN
2011/10/21
We revisit the concept of a blazar sequence that relates the synchrotron peak frequency ({\nu}peak) in blazars with synchrotron peak luminosity (Lpeak, in {\nu}L{\nu}) using a large sample of radio-lo...
Chemical properties in the most distant radio galaxy
galaxies: active – galaxies: nuclei – quasars: emission lines – quasars: general
2011/10/21
We present a deep optical spectrum of TN J0924-2201, the most distant radio galaxy at z = 5.19, obtained with FOCAS on the Subaru Telescope. We successfully detect, for the first time, the CIV1549 emi...
Very Long Baseline Array Imaging of Parsec-scale Jet Structures in Radio-loud Narrow-line Seyfert 1 Galaxies
Long Baseline Array Imaging Radio-loud Narrow-line Seyfert
2011/10/21
We conducted very long baseline interferometry (VLBI) observations of five radio-loud narrow-line Seyfert 1 (NLS1) galaxies in milliarcsecond resolutions at 1.7 GHz (18 cm) using the Very Long Baselin...
The unusual radio transient in M82: an SS 433 analogue?
stars:radio:continuum – stars:X-rays:binaries – Galaxies:individual:M82– X-rays:galaxies
2011/10/19
In this paper we discuss the recently discovered radio transient in the nuclear region of M\,82. It has been suggested that this source is an X-ray binary, which, given the radio flux density, would r...
X-ray Observations of Radio Transients without Optical Hosts
X-ray Observations Radio Transients without Optical Hosts
2011/10/19
We present a 50 ks Chandra ACIS-I X-ray observation of the Bower et al. VLA archival field. The observations reach a limiting sensitivity of ~1E-4 counts/s, corresponding to a flux of a few times 1E-1...
Luminosities of recycled radio pulsars in globular clusters
stars: neutron — pulsars: general — methods:general — globular clusters: individual
2011/10/13
Using Monte Carlo simulations, we model the luminosity distribution of recycled pulsars in globular clusters as the brighter, observable part of an intrinsic distribution and find that the observed lu...
A multiple-beam CLEAN for imaging intra-day variable radio sources
Methods: data analysis – Techniques: image processing – Radio continuum: general
2011/10/13
The CLEAN algorithm, widely used in radio interferometry for the deconvolution of radio images, performs well only if the raw radio image (dirty image) is, to good approximation, a simple convolution ...
Complex Radio Spectral Energy Distributions in Luminous and Ultraluminous Infrared Galaxies
Complex Radio Spectral Energy Distributions Luminous Ultraluminous Infrared
2011/10/12
We use the Expanded Very Large Array to image radio continuum emission from local luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs) in 1 GHz windows centered at 4.7, 7.2, 29, and 36 GHz....
The radio core of the Ultraluminous Infrared Galaxy F00183-7111: watching the birth of a quasar
radio continuum: galaxies-galaxies: evolution-galaxies: ULIRG-galaxies: active-VLBI
2011/10/12
F00183-7111 is one of the most extreme Ultra-Luminous Infrared Galaxies known. Here we present a VLBI image which shows that F00183-7111 is powered by a combination of a radio-loud Active Galactic Nuc...
Radio Imaging of the NGC 1333 IRAS 4A Region: Envelope, Disks, and Outflows of a Protostellar Binary System
ISM: individual (NGC 1333 IRAS 4A) — ISM: jets outfl ows — ISM: binaries: general— stars: formation
2011/10/12
The NGC 1333 IRAS 4A protobinary was observed in the 1.3 cm and 6.9 mm continuum and the ammonia and SiO lines, with an angular resolution of about 0.4 arcseconds. The continuum maps show the circumst...
Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission
Broad Line Radio Galaxies Fermi-LAT:OriginGeV Gamma-Ray Emission
2011/10/10
We report on a detailed investigation of the gamma-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data. We confirm the previously reporte...
The Two-Component Radio Luminosity Function of QSOs: Star Formation and AGN
The Two-Component Luminosity Function Star Formation AGN
2011/10/11
Despite decades of study, it remains unclear whether there are distinct radio-loud and radio-quiet populations of quasi-stellar objects (QSOs). Early studies were limited by inhomogeneous QSO samples,...