Revealing the Unusual Structure of the KAT-7-Discovered Giant Radio Galaxy J0133$-$1302

TL;DR

This study reveals the unusual asymmetric and complex structure of the giant radio galaxy J0133-1302, suggesting recent jet activity and potential GPS characteristics, based on GMRT observations at 323 and 608 MHz.

Contribution

The paper provides the first detailed morphological and spectral analysis of J0133-1302, highlighting its unusual asymmetry, complex lobe structure, and possible new jet activity.

Findings

Lobes are highly asymmetric with the upper lobe being more extended.

The upper lobe shows complex, bent-double-like structures.

The source may be a GigaHertz Peaked Spectrum (GPS) radio galaxy.

Abstract

We present a new study of the 1.7 Mpc KAT-7-discovered giant radio galaxy, J0133$-$1302, which was carried out using GMRT data at 323 and 608 MHz. This source is located at RA $01^h33^m13^s$ and Dec $-13^{\circ}03^\prime00^{\prime\prime}$ and has a photometric redshift of $\sim$0.3. We discovered unusual morphological properties of the source which include lobes that are exceptionally asymmetric, where the upper lobe is much further from the core when compared to the lower lobe, and a complex structure of the upper lobe. This complex structure of the upper lobe hints at the presence of another source, in close proximity to the edge of the lobe, which resembles a bent-double, or distorted bent tail (DBT) radio galaxy. Both the upper lobe and the lower lobe have a steep spectrum, and the synchrotron age of the lower lobe should be less than about 44 Myr. The core has an inverted spectrum, and our results suggest that the parent galaxy in J0133$-$1302 is starting a new jet activity. Our spectral analysis indicates that this source could be a GigaHertz Peaked Spectrum (GPS) radio galaxy.