Implication of Spin Constraints by the Event Horizon Telescope on Stellar Orbits in the Galactic Center

  title={Implication of Spin Constraints by the Event Horizon Telescope on Stellar Orbits in the Galactic Center},
  author={Giacomo Fragione and Abraham Loeb},
  journal={The Astrophysical Journal Letters},
The center of the Milky Way hosts the closest supermassive black hole, Sgr A*. Decades of near-infrared observations of our Galactic Center have shown the presence of a small population of stars (the so-called S-star cluster) orbiting Sgr A*, which were recently reported to be arranged into two orthogonal disks. In this case, the timescale for the Lense–Thirring precession of S stars should be longer than their age, implying a low spin for Sgr A*. In contrast, the recent results by the Event… 
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Twelve Years of Spectroscopic Monitoring in the Galactic Center: The Closest Look at S-stars near the Black Hole
We study the young S-stars within a distance of 0.04 pc from the supermassive black hole in the center of our Galaxy. Given how inhospitable the region is for star formation, their presence is more
2019a, ApJL, 875, L1 Event Horizon
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