Origin of non - keplerian motions of masers in NGC 1068
نویسنده
چکیده
We demonstrate that the “sub-keplerian” rotation curve of maser spots in NGC 1068 can be explained by the gravitational attraction of the disc orbiting the central black hole. Possible parameters matching observations are: black hole mass ≃ (1.2± 0.1) × 10 M⊙, disc outer edge & 1.3 pc, aspect ratio 3× 10 −3 . H R . 0.3, surface density Σ ∝ R , and disc mass ≃ (9.4±1.6)×10 M⊙. The physical conditions required for the excitation of masers are fulfilled, and the outer disc would stand in a gravitationally marginally stable state.
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