2003/06/03 by Brad Hansen, Brad M. S. Hansen, Milos Milosavljevic +1 · 3 citations
Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Binary black hole #Black hole (networking) #Galactic Center #Galaxy #Gravitational wave #Intermediate-mass black hole #Milky Way #Physics #Pulsars and Gravitational Waves Research #Sagittarius A* #Stars #Stellar black hole #Stellar collision #Stellar evolution #Stellar kinematics #Supermassive black hole #astro-ph
paper · pdf · doi:10.1086/378182
5 pages, 2 postscript figures, submitted to ApJ letters The introduction section has been updated since submission to ApJ
arxiv created 2003/06/03 · openalex publication_date 2003/07/16 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Deep infrared observations and long-term monitoring programs have provided dynamical evidence of a supermassive black hole of mass 3 × 10 6 M ☉ associated with the radio source Sagittarius A* at the center of our Galaxy. The brightest stars orbiting within 0.1 pc of the black hole appear to be young, massive main-sequence stars, in spite of an environment near the black hole that is hostile to star formation. We discuss mechanisms by which stars born outside the central parsec can sink toward the black hole and conclude that the drag coming from plausible stellar populations does not operate on the short timescales required by the stellar ages. We propose that these stars were dragged in by a second black hole of mass ~10 3 -10 4 M ☉ , which would be classified as an intermediate-mass black hole. We discuss the implications for the stellar populations and the kinematics in the Galactic center. Finally, we note that continued astrometric monitoring of the central radio source offers us the prospect for a direct detection of such objects.