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arXiv · 2504.02908

Exploring the presence of a fifth force at the Galactic Center

The GRAVITY Collaboration·K. Abd El Dayem·R. Abuter·N. Aimar·P. Amaro Seoane·A. Amorim·J. P. Berger·H. Bonnet·G. Bourdarot·W. Brandner·V. Cardoso·Y. Clénet·R. Davies·P. T. de Zeeuw·A. Drescher·A. Eckart·F. Eisenhauer·H. Feuchtgruber·G. Finger·N. M. Förster Schreiber·A. Foschi·P. Garcia·E. Gendron·R. Genzel·S. Gillessen·M. Hartl·X. Haubois·F. Haussmann·T. Henning·S. Hippler·M. Horrobin·L. Jochum·L. Jocou·A. Kaufer·P. Kervella·S. Lacour·V. Lapeyrère·J. -B. Le Bouquin·P. Léna·D. Lutz·F. Mang·N. More·J. Osorno·T. Ott·T. Paumard·K. Perraut·G. Perrin·S. Rabien·D. C. Ribeiro·M. Sadun Bordoni·S. Scheithauer·J. Shangguan·T. Shimizu·J. Stadler·O. Straub·C. Straubmeier·E. Sturm·L. J. Tacconi·I. Urso·F. Vincent·S. D. von Fellenberg·E. Wieprecht·J. Woillez
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Abstract

Aims: The presence of a Yukawa-like correction to Newtonian gravity is investigated at the Galactic Center, leading to a new upper limit for the intensity of such a correction. Methods: We perform a Markov Chain Monte Carlo analysis using the astrometric and spectroscopic data of star S$2$ collected at the Very Large Telescope by GRAVITY, NACO and SINFONI instruments, covering the period from $1992$ to $2022$. Results: The precision of the GRAVITY instrument allows us to derive the most stringent upper limit at the Galactic Center for the intensity of the Yukawa contribution ($\propto \, \alpha e^{- \lambda r}$) to be $|\alpha| < 0.003$ for a scale length $\lambda = 3 \cdot 10^{13}\, \rm m\, (\sim 200 \, \rm AU)$. This improves by roughly one order of magnitude all estimates obtained in previous works.

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The GRAVITY Collaboration, K. Abd El Dayem, R. Abuter, N. Aimar, P. Amaro Seoane, A. Amorim, J. P. Berger, H. Bonnet, G. Bourdarot, W. Brandner, V. Cardoso, Y. Clénet, R. Davies, P. T. de Zeeuw, A. Drescher, A. Eckart, F. Eisenhauer, H. Feuchtgruber, G. Finger, N. M. Förster Schreiber, A. Foschi, P. Garcia, E. Gendron, R. Genzel, S. Gillessen, M. Hartl, X. Haubois, F. Haussmann, T. Henning, S. Hippler, M. Horrobin, L. Jochum, L. Jocou, A. Kaufer, P. Kervella, S. Lacour, V. Lapeyrère, J. -B. Le Bouquin, P. Léna, D. Lutz, F. Mang, N. More, J. Osorno, T. Ott, T. Paumard, K. Perraut, G. Perrin, S. Rabien, D. C. Ribeiro, M. Sadun Bordoni, S. Scheithauer, J. Shangguan, T. Shimizu, J. Stadler, O. Straub, C. Straubmeier, E. Sturm, L. J. Tacconi, I. Urso, F. Vincent, S. D. von Fellenberg, E. Wieprecht, J. Woillez. 2025-04-03. Exploring the presence of a fifth force at the Galactic Center. https://doi.org/10.1051/0004-6361%2F202554676

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