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Register a new userA Triple AGN in the NGC 7733-7734 Merging Group
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Authors
Jyoti Yadav
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Context: Galaxy interactions and mergers can lead to supermassive black hole (SMBH) binaries which become active galactic nuclei (AGN) pairs when the SMBHs start accreting mass. If there is a third galaxy involved in the interaction, then a triple AGN system can form. Aims: Our goal is to investigate the nature of the nuclear emission from the galaxies in the interacting pair NGC,7733--NGC,7734 using archival VLT/MUSE Integral field spectrograph data and study its relation to the stellar mass distribution traced by near-infrared (NIR) observations from the South African Astronomical Observatory (SAAO). Methods:We conducted near-infrared observations using the SAAO and identified the morphological properties of bulges in each galaxy. We used MUSE data to obtain a set of ionized emission lines from each galaxy and studied the ionization mechanism. We also examined the relation of the galaxy pair with any nearby companions with Far-UV observations using the UVIT. Conclusions: The emission line analysis from the central regions of NGC,7733 and NGC,7734 show Seyfert and LINER type AGN activity. The galaxy pair NGC,7733--34 also shows evidence of a third component, which has Seyfert-like emission. Hence, the galaxy pair NGC,7733--34 forms a triple AGN system. We also detected an Extended Narrow-line region (ENLR) associated with the nucleus of NGC,7733.
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