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arXiv · 1612.06452

Tale of J1328+2752: a misaligned double-double radio galaxy hosted by a binary black-hole?

S. Nandi·M. Jamrozy·R. Roy·J. Larsson·D. J. Saikia·M. Baes·M. Singh
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Abstract

We present a radio and optical study of the double-double radio galaxy J1328+2752 based on new low-frequency GMRT observations and SDSS data. The radio data were used to investigate the morphology and to perform a spectral index analysis. In this source we find that the inner double is misaligned by $\sim$30$^\circ$ from the axis of the outer diffuse structure. The SDSS spectrum shows that the central component has double-peaked line profiles with different emission strengths. The average velocity off-set of the two components is 235$\pm$10.5 km s$^{-1}$. The misaligned radio morphology along with the double-peaked emission lines indicate that this source is a potential candidate binary supermassive black hole. This study further supports mergers as a possible explanation for repeated jet activity in radio sources.

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S. Nandi, M. Jamrozy, R. Roy, J. Larsson, D. J. Saikia, M. Baes, M. Singh. 2016-12-19. Tale of J1328+2752: a misaligned double-double radio galaxy hosted by a binary black-hole?. https://doi.org/10.1093/mnrasl%2Fslw256

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