Stellar rotation as a new observable to test general relativity in the Galactic Center

Abstract

S-stars in the Galactic Center are excellent testbeds of various general relativistic effects. While previous works focus on modeling their orbital motion around Sgr A*--the supermassive black hole in the Galactic Center--here we explore the possibility of using the rotation of S-stars to test the de Sitter precession predicted by general relativity. We show that by reorienting the rotation axes of S-stars, de Sitter precession will change the apparent width of the absorption lines in the stellar spectra. Our numerical simulations suggest that the newly discovered S4714 and S62 are best suited for such a test because of their small pericenter distances relative to Sgr A*. Depending on the initial inclination of the star, the line width would vary by as much as $20-76\mathrm{km}{\mathrm{s}}^{-1}$ within a period of $20-40$ years. Such a variation is comparable to the current detection limit. Since the precession rate is sensitive to the orbital eccentricity and stellar quadrupole structure, monitoring the rotation of S-stars could also help us better constrain the orbital elements of the S-stars and their internal structures.

arXiv comment5 pages, 3 figures. Comments welcome!

References in corpus (25)

• Observation of Gravitational Waves from a Binary Black Hole Merger
• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies
• GWTC-1: A Gravitational-Wave Transient Catalog of Compact Binary Mergers Observed by LIGO and Virgo during the First and Second Observing Runs
• Measuring Distance and Properties of the Milky Way's Central Supermassive Black Hole with Stellar Orbits
• Revisiting the Scaling Relations of Black Hole Masses and Host Galaxy Properties
• The Galactic Center Massive Black Hole and Nuclear Star Cluster
• Closest Star Seen Orbiting the Supermassive Black Hole at the Centre of the Milky Way
• Tests of general relativity from timing the double pulsar
• Detection of the gravitational redshift in the orbit of the star S2 near the Galactic centre massive black hole
• Detection of the Schwarzschild precession in the orbit of the star S2 near the Galactic centre massive black hole
• Relativistic redshift of the star S0-2 orbiting the Galactic center supermassive black hole
• An Improved Distance and Mass Estimate for Sgr A* from a Multistar Orbit Analysis
• Testing General Relativity with stellar orbits around the supermassive black hole in our Galactic center
• Testing the general relativistic ''no-hair'' theorems using the galactic center black hole SgrA*
• The Shortest Known Period Star Orbiting our Galaxy's Supermassive Black Hole
• Testing Properties of the Galactic Center Black Hole Using Stellar Orbits
• Probing the Spacetime Around Sgr A* with Radio Pulsars
• First-post-Newtonian quadrupole tidal interactions in binary systems
• On the nature of the fast moving star S2 in the Galactic Center
• S62 and S4711: Indications of a population of faint fast moving stars inside the S2 orbit -- S4711 on a 7.6 year orbit around Sgr~A*
• A hidden friend for the galactic center black hole, Sgr A*
• Pulsars as probes of gravity and fundamental physics
• The geodesic motion of S2 and G2 as a test of the fermionic dark matter nature of our galactic core
• Evolution of rotation in rapidly rotating early-type stars during the main sequence with 2D models

Cited by in corpus (3)

• Constraints on self-dual black hole in loop quantum gravity with S0-2 star in the Galactic Center
• Revisiting Stellar Orbits and the Sgr A${}^{\ast }$ Quadrupole Moment
• Analytic Post-Newtonian Astrometric and Spectroscopic Models of Orbits around Black Holes