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arXiv · 1008.1720

Long-term classical and general relativistic effects on the radial velocities of the stars orbiting Sgr A*

Lorenzo Iorio
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Abstract

We analytically work out the cumulative, i.e. averaged over one orbital revolution, time variations of the radial velocity v_r of a typical S star orbiting the Supermassive Black Hole (SBH) hosted by the Galactic Center (GC) in Sgr A* caused by several dynamical effects. They are the general relativistic gravitoelectromagnetic (GEM) fields of the SBH, its quadrupole mass moment Q2, and a diffuse dark matter distribution around the SBH. All of them induce non-zero secular radial accelerations proportional to the eccentricity e of the orbit. By taking the S2 star, orbiting the SBH along a highly eccentric (e = 0.8831) ellipse with a period Pb = 15.9 yr, we numerically compute the magnitudes of its radial accelerations (Abridged).

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BibTeXRIS

Lorenzo Iorio. 2010-08-10. Long-term classical and general relativistic effects on the radial velocities of the stars orbiting Sgr A*. https://doi.org/10.1111/j.1365-2966.2010.17701.x

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