Naslov
LOFAR Deep Fields: probing a broader population of polarized radio galaxies in ELAIS-N1

Autori
Herrera Ruiz, N. ; O’Sullivan, S. P. ; Vacca, V. ; Jelić, Vibor ; Nikiel- Wroczyński, B. ; Bourke, S. ; Sabater, J. ; Dettmar, R.-J. ; Heald, G. ; Horellou, C. ; Piras, S. ; Sobey, C. ; Shimwell, T. W. ; Tasse, C. ; Hardcastle, M. J. ; Kondapally, R. ; Chyży, K. T. ; Iacobelli, M. ; Best, P. N. ; Brüggen, M. ; Carretti, E. ; Prandoni, I.

Izvornik
Astronomy & astrophysics (Berlin) (0004-6361) 648 (2021); A12, 14

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
polarization ; galaxies: individual: ELAIS-N1 ; radio continuum: galaxies ; techniques: polarimetric

Sažetak
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.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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