Line emission from another relativistic accretion disk - 3C 332

Observational and theoretical investigations are reviving interest in the hypothesis that the broad emission lines in some AGN might arise in a relativistic accretion disk. But until now only one object, Arp 102B, has displayed the distinctive double-peaked, asymmetric line shape which is fitted well by the disk model. This paper reports the discovery of a line profile in a second radio galaxy, 3C 332 (z = 0.1511), which is so similar to that of Arp 102B as to suggest the existence of a small but distinct class of objects in which the broad emission lines arise largely in the disk. In the context of the model, the line-emitting region in 3C 332 lies between r1 of about 175 and r2 of about 525r(g). In comparison, the line profile of Arp 102B is fitted with r1 of about 350 and r2 of about 1000. All aspects of the model developed for Arp 102B are consistent with the properties of 3C 332. 24 refs