The Need for a Second Black Hole at the Galactic Center

摘要: Deep infrared observations and long-term monitoring programs have provided dynamical evidence of a supermassive black hole mass 3 × 106 M☉ associated with the radio source Sagittarius A* at center our Galaxy. The brightest stars orbiting within 0.1 pc appear to be young, massive main-sequence stars, in spite an environment near that is hostile star formation. We discuss mechanisms by which born outside central parsec can sink toward conclude drag coming from plausible stellar populations does not operate on short timescales required ages. propose these were dragged second ~103-104 M☉, would classified as intermediate-mass hole. implications for kinematics Galactic center. Finally, we note continued astrometric offers us prospect direct detection such objects.