“Winged” Radio Sources from the LOFAR Two-meter Sky Survey First Data Release (LoTSS DR1)

Abstract

A small number of extragalactic radio sources disclose a pair of low-surface-brightness radio lobes, known as “wings,” aligned at a certain angle to the primary jets. Such exotic sources are known as “winged” radio sources. Here we report the new identification of a total of 26 “winged” radio sources from the LOFAR Two-meter Sky Survey First Data Release (LoTSS DR1). Out of the 26 “winged” sources, 14 are identified as X-shaped radio galaxies and the remaining 12 as Z-shaped radio galaxies. The available optical counterpart of each radio galaxy is cataloged along with its estimated redshift. Among the 26 sources, 15 candidates are classified as FR-II radio galaxies, and two are classified as FR-I type. For nine candidates, no conclusions are drawn due to their complex morphology. We also calculate the physical parameters such as spectral index, radio luminosity, and power of the sources. We have made a statistical study of the spectral index by combining our estimated value with the spectral index collected from previous works. A mean value of spectral index of 0.71 is obtained.