Abstract Active galactic nuclei (AGN) are the compact, energetic central regions of galaxies, powered by supermassive black holes that accrete surrounding gas and dust. Their optical spectra can be identified by strong emission-line signatures (broad and/or narrow lines). Those showing only narrow lines are classified as ‘Type 2’ AGN. Extensive surveys like SDSS cover AGN in the Northern Sky, but the equivalent coverage in the Southern Sky remains limited. We address this by presenting a new catalogue of Type 2 AGN from the 6dF Galaxy Survey (6dFGS), which has 136 304 spectra covering ∼17 000 deg2, mainly of low redshift galaxies. We use a Median Absolute Deviation (MAD) cut on the continuum-fitted spectrum to select emission line galaxies. AGN were identified by fitting the 6dFGS spectra with a Python QSO fitting tool (PyQSOFit). All selected spectra were visually inspected and corrected for fitting errors where necessary. 10 503 narrow emission line galaxies were identified in 6dFGS, including 5002 Type 2 AGN classified from Baldwin–Phillips–Terlevich (BPT) diagram. They have a median redshift of z ∼ 0. 032 and a median O iii luminosity of (L ₎₈₈₈/ ergs~s^-1) 40. 02.
Suresh et al. (Thu,) studied this question.