https://hal-insu.archives-ouvertes.fr/insu-03645854Sadeghian, LalehLalehSadeghianWill, Clifford M.Clifford M.WillIAP - Institut d'Astrophysique de Paris - INSU - CNRS - Institut national des sciences de l'Univers - SU - Sorbonne Université - CNRS - Centre National de la Recherche ScientifiqueTesting the black hole no-hair theorem at the galactic center: perturbing effects of stars in the surrounding clusterHAL CCSD2011General Relativity and Quantum CosmologyAstrophysics - Galaxy Astrophysics[SDU] Sciences of the Universe [physics]Gestionnaire, Hal Sorbonne Université2022-04-19 16:21:122023-03-24 14:53:262022-04-19 16:21:12enJournal articles10.1088/0264-9381/28/22/2250291Observations of the precessing orbits of stars very near the massive black hole in the galactic center could provide measurements of the spin and quadrupole moment of the hole and thereby test the no-hair theorem of general relativity. Since the galactic center is likely to be populated by a distribution of stars and small black holes, their gravitational interactions will perturb the orbit of any given star. We estimate the effects of such perturbations using analytic orbital perturbation theory, and show that for a range of possible stellar distributions, and for an observed star sufficiently close to the black hole, the relativistic spin and quadrupole effects of a rapidly spinning hole will be larger than the effects of stellar cluster perturbations. Our results are consistent with those from recent numerical N-body simulations by Merritt et al.