Revealing the unusual structure of the KAT-7-discovered giant radio galaxy J0133−1302

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.
13 pages, 15 figures. To be published in the Monthly Notices of the Royal Astronomical Society (MNRAS)