Work

Probing departures from Schwarzschild geometry with the S301 star and kilometre-baseline interferometry

Year: 2026

Type: preprint

Abstract: The S301 star reaches a pericentre one tenth that of S2, opening a new regime for probing black-hole spin and departures from Schwarzschild. We develop a post-Newtonian secular Hamiltonian framework for bound geodesics in stationary, axisymmetric spacetimes and compute the maximum projected astrometric deviation over one orbit. At the expected GRAVITY+ precision, S301 can probe several nonrotating geometries and sizeable spin-induced deviations, while kilometre-baseline interferometry can probe much smaller departures, establishing S301 as a powerful test of the spacetime geometry of Sgr A*.

Source: arXiv (Cornell University)

DOI: 10.48550/arxiv.2610.07123

Authors: Silva, Rodrigo P., Correia, Alexandre C. M., Garcia, Paulo J. V.

Institution: University of Coimbra

Language: English

Topic: Astrophysical Phenomena and Observations

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Universidade de Lisboa, Fundação para a Ciência e a Tecnologia

Awards: Centro de Física da Universidade de Coimbra, G1607172680, G1828757707, G2285047463, Centro de Astrofísica e Gravitação, Centro de Astrofísica e Gravitação, Probing the nature of SgrA* with stellar dynamics

OpenAlex ID: W7220969579

Cites: 36

Cited by: 1

Related to: 10