Fine structure of the nucleus of the galaxy NGC 1275

Аннотация

The fine structure of the nucleus of the Seyfert galaxy NGC 1275 was investigated in 2005–2010 at a wavelength of 2 cm with a resolution as high as 50 μas. The structure consists of two parallel identical systems, eastern and western, spaced 0.5 pc apart in the plane of the sky. Each of them contains an ejector and a bipolar outflow. There are extended regions, lobes, at the extension of the bipolar outflows in the −10° and 170° directions at distances of 5 pc northward and 6.5 pc southward of the active zone. The observed difference between the jet and counterjet sizes by a factor of ~3 and between the distances to the lobes by a factor of 0.8 is determined by the difference between their velocities and by the change of sign of the outflow acceleration in the period of silence. The high-velocity bipolar outflows are surrounded by three pairs of low-velocity components. The diameters of the low-velocity coaxial outflows and the third component are Ø₁ ≈ 0.3 pc, Ø₂ ≈ 0.8 pc, and Ø₃ ≈ 1.4 pc at the detection limit. The outer low-velocity components of the outflows encompass both high-velocity outflows. The velocities of the outflows and their brightness temperatures increase exponentially as the center of the high-velocity outflows is approached. The brightness temperatures of the high-velocity outflows at the ejector exit are T_b > 1012 K. The spectral line velocities in the nuclear region differ by ~600 km s⁻¹ due to the velocity difference between the two systems. In the case of Keplerian motion, the revolution period is ~5 × 10³ yr, and the mass of the central massive bodies, black holes, is M ≈ 10⁷M_⊙. The fine structure suggests a vortical nature of the formation. In the case under consideration, two parallel vortices spaced ~0.5 pc apart and shifted by ~0.5 pc relative to each other were formed. The surrounding material inflows onto the disk of each system, is transferred in a spiral to the center, and is ejected in the −10° and 170° directions as an excess angular momentum is accumulated. The interaction with the surrounding medium accelerates and collimates the rotating outflows. The residual material falls to the forming central massive body, a black hole, whose gravitational field stabilizes and accelerates the system formation process.