Bardeen Petterson effect and the disk structure of the seyfert galaxy ngc 1068

• Processo: 07/02760-1
• Modalidade de apoio: Auxílio à Pesquisa - Publicações científicas - Artigo
• Data de Início da vigência: 01 de junho de 2007
• Data de Término da vigência: 31 de outubro de 2007
• Área do conhecimento: Ciências Exatas e da Terra - Astronomia - Astrofísica Extragaláctica
• Pesquisador responsável: Anderson Caproni
• Beneficiário: Anderson Caproni
• Instituição Sede: Centro de Ciências Exatas e Tecnológicas. Universidade Cruzeiro do Sul (UNICSUL). São Paulo , SP, Brasil
• Assunto(s): Buracos negros Discos de acresção Núcleos ativos de galáxias Jatos (astronomia) Publicações de divulgação científica Artigo científico
• Palavra(s)-Chave do Pesquisador: buracos negros | Discos de Acresção | Jatos | Ngc 1068 | núcleos ativos de galáxias | Núcleos ativos de galáxias

Resumo

VLBA high spatial resolution observations of the disk structure of the active galactic nucleus (AGN) NGC 1068 have recently revealed that the kinematics and geometry of this AGN is well characterized by an outer disk of H2O maser emission having a compact milliarcsecond-(parsec) scale structure, which is encircling a thin rotating inner disk surrounding a about 10to7 Mo compact mass, likely a black hole. A curious feature in this source is the occurrence of a misalignment between the inner and outer parts of the disk, with the galaxys radio jet being orthogonal to the inner disk. We interpret this peculiar configuration as due to the Bardeen-Petterson effect, a general relativistic effect that warps an initially inclined (to the black hole equator) viscous disk and drives the angular momentum vector of its inner part into alignment with the rotating black hole spin. We estimate the timescale for both angular momentato get aligned as a function of the spin parameter of the Kerr black hole. We also reproduce the shape of the parsec andkiloparsec-scale jets, assuming a model in which the jet is precessing with a period and aperture angle that decrease exponentially with time, as expected from the Bardeen-Petterson effect. (AU)