Lofar deep fields: Probing a broader population of polarized radio galaxies in elais-n1
Journal article, 2021

We present deep polarimetric observations of the European Large Area ISO Survey-North 1 (ELAIS-N1) field using the Low Frequency Array (LOFAR) at 114.9-177.4 MHz. The ELAIS-N1 field is part of the LOFAR Two-metre Sky Survey deep fields data release I. For six eight-hour observing epochs, we align the polarization angles and stack the 20″-resolution Stokes Q, U-parameter data cubes. This produces a 16 deg2 image with 1σQU sensitivity of 26 μJy beam-1 in the central area. In this paper, we demonstrate the feasibility of the stacking technique, and we generate a catalog of polarized sources in ELAIS-N1 and their associated Faraday rotation measures (RMs). While in a single-epoch observation we detect three polarized sources, this number increases by a factor of about three when we consider the stacked data, with a total of ten sources. This yields a surface density of polarized sources of one per 1.6 deg2. The Stokes I images of three of the ten detected polarized sources have morphologies resembling those of FR I radio galaxies. This represents a greater fraction of this type of source than previously found, which suggests that more sensitive observations may help with their detection.

Techniques: Polarimetric

Polarization

Radio continuum: Galaxies

Galaxies: Individual: ELAIS-N1

Author

N. Herrera Ruiz

Ruhr-Universität Bochum

Shane P. O'Sullivan

Dublin City University

V. Vacca

INAF Osservatorio Astronomico di Cagliari

V. Jelić

Ruder Boskovic Institute

B. Nikiel-Wroczyński

Jagiellonian University in Kraków

Stephen Bourke

Chalmers, Space, Earth and Environment, Onsala Space Observatory, Observation Support

J. Sabater

Royal Observatory

R. -J. Dettmar

Ruhr-Universität Bochum

G. Heald

CSIRO Astronomy and Space Science

Cathy Horellou

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Sara Piras

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Extragalactic Astrophysics

C. Sobey

CSIRO Astronomy and Space Science

T. W. Shimwell

Netherlands Institute for Radio Astronomy (ASTRON)

C. Tasse

Rhodes University

Observatoire de Paris-Meudon

Centre national de la recherche scientifique (CNRS)

M. J. Hardcastle

University of Hertfordshire

R. Kondapally

Royal Observatory

K.T. Chyz̊y

Jagiellonian University in Kraków

M. Iacobelli

Netherlands Institute for Radio Astronomy (ASTRON)

P. N. Best

Royal Observatory

M. Brueggen

University of Hamburg

E. Carretti

INAF OAS Bologna

I. Prandoni

INAF OAS Bologna

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 648 A12

Subject Categories

Astronomy, Astrophysics and Cosmology

Atom and Molecular Physics and Optics

Geophysics

DOI

10.1051/0004-6361/202038896

More information

Latest update

7/9/2021 9