Winged Radio Sources from LOFAR Two-metre Sky Survey First Data Release (LoTSS DR1)

TL;DR

This paper reports the discovery and analysis of 33 winged radio sources, including X-shaped and Z-shaped galaxies, from the LOFAR survey, providing insights into their physical properties and morphology.

Contribution

It is the first large-scale identification and characterization of winged radio sources from LOFAR data, expanding knowledge of their spectral and morphological features.

Findings

33 winged radio sources identified, including 21 XRGs and 12 ZRGs.

Majority have steep radio spectra, typical of lobe-dominated galaxies.

Optical counterparts found for most sources, enabling further study.

Abstract

Winged radio sources are a small sub-class of extragalactic radio sources which display a pair of low surface brightness radio lobes, known as `wings' aligned at a certain angle with the primary jets. Depending on the location of wings, these galaxies look like X or Z and are known as X-shaped Radio Galaxy (XRG) or Z-shaped Radio Galaxy (ZRG). We report the identification of 33 winged radio sources from the LOFAR Two-metre Sky Survey First Data Release (LoTSS DR1) out of which 21 sources are identified as X-shaped radio galaxies and 12 as Z-shaped radio galaxies. Optical counterparts are identified for 14 XRGs (67 per cent) and 12 ZRGs (100 per cent). We studied various physical parameters of these sources like spectral index, radio luminosity, and power. The radio spectrum of the majority of XRGs and ZRGs is steep ($\alpha_{1400}^{144}>0.5$), which is typical of lobe dominated radio galaxies. The statistical studies are done on the relative size of the major and minor axes and the angle between the major axis and minor axis for XRGs.