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The NRAO VLA Sky Survey (NVSS) Rotation Measure (RM) catalogue is invaluable for the study of cosmic magnetism. However, the RM values reported in it can be affected by n$\pi$-ambiguity, resulting in deviations of the reported RM from the…

Astrophysics of Galaxies · Physics 2019-05-22 Yik Ki Ma , S. A. Mao , Jeroen Stil , Aritra Basu , Jennifer West , Carl Heiles , Alex S. Hill , S. K. Betti

Based on a sample of 355 quasars with significant optical polarization, we found that quasar polarization vectors are not randomly oriented over the sky as naturally expected. The probability that the observed distribution of polarization…

Astrophysics · Physics 2014-01-22 D. Hutsemekers , A. Payez , R. Cabanac , H. Lamy , D. Sluse , B. Borguet , J. -R. Cudell

We present the first results of the VLBA Imaging and Polarimetry Survey (VIPS), a 5 GHz VLBI survey of 1,127 sources with flat radio spectra. Through automated data reduction and imaging routines, we have produced publicly available I, Q,…

We present a detailed statistical analysis of the alignment of polarizations of radio sources at high redshift. We use the JVAS/CLASS 8.4-GHz surveys for our study. This study is motivated by the puzzling signal of alignment of…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Prabhakar Tiwari , Pankaj Jain

We measure the angular two-point correlation and angular power spectrum from the NRAO VLA Sky Survey (NVSS) of radio galaxies. They are found to be consistent with the best-fit cosmological model from the Planck analysis, and with the…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-29 Song Chen , Dominik J. Schwarz

The goals of this work are to provide NIR polarimetry of the stellar sources in the central pc at the resolution of an 8m telescope for the first time, along with new insights into the nature of the known bright bow-shock sources. We use AO…

Astrophysics of Galaxies · Physics 2015-05-28 Rainer M. Buchholz , Gunther Witzel , Rainer Schödel , Andreas Eckart , Markus Bremer , Koraljka Muzic

We study the polarisation properties of extragalactic sources at 95 and 150 GHz in the SPTpol 500 deg$^2$ survey. We estimate the polarised power by stacking maps at known source positions, and correct for noise bias by subtracting the mean…

Detection of point sources in images is a fundamental operation in astrophysics, and is crucial for constraining population models of the underlying point sources or characterizing the background emission. Standard techniques fall short in…

Instrumentation and Methods for Astrophysics · Physics 2018-02-28 Tansu Daylan , Stephen K. N. Portillo , Douglas P. Finkbeiner

We use the fourth data release of the Sloan Digital Sky Survey to investigate the orientations of 4289 satellite galaxies with respect to their hosts. The orientation of the satellites is inconsistent with a random distribution at the…

Astrophysics · Physics 2009-11-11 Ingolfur Agustsson , Tereasa G. Brainerd

Stacking polarized radio emission in SKA surveys provides statistical information on large samples that is not accessible otherwise due to limitations in sensitivity, source statistics in small fields, and averaging over frequency…

Instrumentation and Methods for Astrophysics · Physics 2015-01-05 J. M. Stil , B. W. Keller

We cross-identified the ROSAT Bright Source Catalog (RBSC) and the NRAO VLA Sky Survey (NVSS) to construct the RBSC-NVSS sample of the brightest X-ray sources (>= 0.1 counts/s or ~1E-12 ergs/cm/cm/s in the 0.1-2.4 keV band) that are also…

Astrophysics · Physics 2009-10-31 F. E. Bauer , J. J. Condon , T. X. Thuan , J. J. Broderick

In the present paper we study the radio sources in the NRAO VLA SKY Survey (NVSS) analysing its power spectrum and galaxy distribution. There is a discrepancy between the theoretical models in the literature and the data at large scales. A…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-03 A. Marcos-Caballero , P. Vielva , E. Martinez-Gonzalez , F. Finelli , A. Gruppuso , F. Schiavon

Various studies have laid claim to finding an alignment of the polarization vectors or radio jets of active galactic nuclei (AGN) over large distances, but these results have proven controversial and so far, there is no clear explanation…

With the forthcoming release of high precision polarization measurements, such as from the Planck satellite, the metrology of polarization needs to improve. In particular, it is crucial to take into account full knowledge of the noise…

Instrumentation and Methods for Astrophysics · Physics 2015-02-11 L. Montier , S. Plaszczynski , F. Levrier , M. Tristram , D. Alina , I. Ristorcelli , J. -P. Bernard

We present radio intensity and polarisation profiles of 28 $\gamma$-ray-detected pulsars with the aim of putting constraints on their viewing geometries using data from the Parkes telescope. Constraints are formed both from the…

High Energy Astrophysical Phenomena · Physics 2015-06-23 S. C. Rookyard , P. Weltevrede , S. Johnston

In Stage-IV imaging surveys, a significant amount of the cosmologically useful information is due to sources whose images overlap with those of other sources on the sky. The cosmic shear signal is primarily encoded in the estimated shapes…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-04 Javier Sanchez , Ismael Mendoza , David P. Kirkby , Patricia R. Burchat

We present a polarization catalog of 533 extragalactic radio sources with 2.3 GHz total intensity above 420 mJy from the S-band Polarization All Sky Survey, S-PASS, with corresponding 1.4 GHz polarization information from the NRAO VLA Sky…

Astrophysics of Galaxies · Physics 2016-09-21 Mehdi Lamee , Lawrence Rudnick , Jamie S. Farnes , Ettore Carretti , B. M. Gaensler , Marijke Haverkorn , Sergio Poppi

We identified 97 strong pulsars from the NRAO VLA Sky Survey (NVSS) at 1.4 GHz north of Dec(J2000) $>-40\degr$. The total flux density, linear polarization intensity and polarization angle (PA) of all pulsars are extracted from the NVSS…

Astrophysics · Physics 2015-06-24 J. L. Han , W. W. Tian

Radio polarization measurements of pulsed emission from pulsars offer a valuable insight into the basic geometry of the neutron star: inclination angle between the magnetic and rotation axis and inclination of the line of sight. So far, all…

High Energy Astrophysical Phenomena · Physics 2017-01-11 J. Pétri

We performed an integrated optical polarization survey of 70 nearby galaxies to study the relationship between linear polarization and galaxy properties. To date this is the largest survey of its kind. The data were collected at McDonald…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Amy Jones , Lifan Wang , Kevin Krisciunas , Emily Freeland