https://doi.org/10.1140/epjc/s10052-026-15538-x
Regular Article - Theoretical Physics
Spinning particles around Einstein-geometric Proca AdS compact objects
1
Institute of Fundamental and Applied Research, National Research University TIIAME, Kori Niyoziy 39, 100000, Tashkent, Uzbekistan
2
University of Tashkent for Applied Sciences, Str. Gavhar 1, 100149, Tashkent, Uzbekistan
3
Department of Basic Sciences, İstinye University, 34396, Istanbul, Turkey
4
Faculty of Engineering and Natural Sciences, Sabancı University, 34956, Istanbul, Turkey
5
Astrophysics Research Center, The Open University of Israel, 4353701, Raanana, Israel
6
Kimyo International University in Tashkent, Shota Rustaveli str. 156, 100121, Tashkent, Uzbekistan
7
Research Center of Astrophysics and Cosmology, Khazar University, 41 Mehseti Street, AZ1096, Baku, Azerbaijan
8
School of Physics, Harbin Institute of Technology, 150001, Harbin, People’s Republic of China
9
Andijan State University, Universitet Str. 129, 170100, Andijan, Uzbekistan
10
Tashkent State Technical University, 100095, Tashkent, Uzbekistan
a
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Received:
19
November
2025
Accepted:
8
March
2026
Published online:
26
March
2026
Abstract
We investigate the dynamics of spinning test particles in the vicinity of Einstein-geometric Proca (EGP) Anti-de Sitter (AdS) compact objects, which arise from metric-Palatini gravity extended by the antisymmetric part of the affine curvature. Using the Mathisson–Papapetrou–Dixon (MPD) equations with the Tulczyjew spin supplementary condition, we derive the effective potential and analyze the equatorial motion of spinning particles. The influence of the model parameters 
, 
, and the Proca mass parameter 
on the innermost stable circular orbits (ISCO), superluminal spin bounds, and orbital stability is systematically explored. Our results show that increasing and reduces the ISCO radius, angular momentum, and energy, while spin orientation introduces significant modifications to orbital behavior. We further examine head-on collisions of spinning particles near the horizon and demonstrate how the center-of-mass energy depends on spin and the EGP theory parameters. The study reveals that Einstein-geometric Proca AdS black holes may act as efficient particle accelerators, with distinctive features absent in Schwarzschild or standard AdS backgrounds. These findings provide new insights into the interplay between spin dynamics, modified gravity, and strong-field compact object physics.
© The Author(s) 2026
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Funded by SCOAP3.
