We report the virial measurements of the black hole (BH) mass of a sample of 17 type 2 active galactic nuclei (AGN), drawn from the Swift/BAT 70-month 14–195 keV hard X-ray catalogue, where a faint BLR component has been measured via deep NIR (0.8–2.5 μm) spectroscopy. We compared the type 2 AGN with a control sample of 33 type 1 AGN. We find that the type 2 AGN BH masses span the 5 < log(MBH/M⊙) < 7.5 range, with an average log(MBH/M⊙) = 6.7, which is ∼0.8 dex smaller than found for type 1 AGN. If type 1 and type 2 AGN of the same X-ray luminosity log(L14−195/erg s−1) ∼ 43.5 are compared, type 2 AGN have 0.5 dex smaller BH masses than type 1 AGN. Although based on few tens of objects, this result disagrees with the standard AGN unification scenarios in which type 1 and type 2 AGN are the same objects observed along different viewing angles with respect to a toroidal absorbing material.
Onori, F., Ricci, F., LA FRANCA, F., Bianchi, S., Bongiorno, A., Brusa, M., et al. (2017). Detection of faint broad emission lines in type 2 AGN – II. On the measurement of the black hole mass of type 2 AGN and the unified model. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY. LETTERS, 468(1), L97-L102 [10.1093/mnrasl/slx032].
Detection of faint broad emission lines in type 2 AGN – II. On the measurement of the black hole mass of type 2 AGN and the unified model
ONORI, FRANCESCA;RICCI, FEDERICA;LA FRANCA, Fabio;BIANCHI, STEFANO;Brusa, Marcella;Fiore, Fabrizio;MAIOLINO, ROBERTO;Marconi, Alessandro;
2017-01-01
Abstract
We report the virial measurements of the black hole (BH) mass of a sample of 17 type 2 active galactic nuclei (AGN), drawn from the Swift/BAT 70-month 14–195 keV hard X-ray catalogue, where a faint BLR component has been measured via deep NIR (0.8–2.5 μm) spectroscopy. We compared the type 2 AGN with a control sample of 33 type 1 AGN. We find that the type 2 AGN BH masses span the 5 < log(MBH/M⊙) < 7.5 range, with an average log(MBH/M⊙) = 6.7, which is ∼0.8 dex smaller than found for type 1 AGN. If type 1 and type 2 AGN of the same X-ray luminosity log(L14−195/erg s−1) ∼ 43.5 are compared, type 2 AGN have 0.5 dex smaller BH masses than type 1 AGN. Although based on few tens of objects, this result disagrees with the standard AGN unification scenarios in which type 1 and type 2 AGN are the same objects observed along different viewing angles with respect to a toroidal absorbing material.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
