English

Faraday Depolarization Study of a Radio Galaxy Using LOFAR Two-metre Sky Survey: Data Release 2

Cosmology and Nongalactic Astrophysics 2026-02-12 v3

Abstract

We present a detailed depolarization analysis of the radio galaxy \texttt{ILTJ012215.21+254334.8} using polarimetric data from the \textit{LOFAR Two-metre Sky Survey} (LoTSS) Data Release 2 (DR2) catalogue. This source, with \textit{RM} \sim 47 rad m2^{-2} and projected linear size \sim 335 kpc at z0.05z \approx 0.05, serves as a pilot for systematic QU-fitting of unresolved LoTSS sources, building on prior single-target studies that established the need for multi-component Faraday models in complex magneto-ionic media. Fitting five depolarization models to the LoTSS HBA (120-168 MHz) fractional polarization spectra reveals a decisively preferred three-component model (one Faraday-thin instrumental leakage, plus two external Faraday dispersions), demonstrating that LoTSS data alone can constrain moderate Faraday complexity in typical DR2 galaxies. Our results highlight turbulence and inhomogeneity in the foreground magneto-ionic medium and outline a path for population studies of LoTSS FR-I sources.

Keywords

Cite

@article{arxiv.2510.00440,
  title  = {Faraday Depolarization Study of a Radio Galaxy Using LOFAR Two-metre Sky Survey: Data Release 2},
  author = {Samantha Sneha Paul and Abhik Ghosh},
  journal= {arXiv preprint arXiv:2510.00440},
  year   = {2026}
}

Comments

13 pages, 6 figures, 4 tables, published in the Open Journal of Astrophysics