Neural network analysis of S2-star dynamics: extended mass N. Galikyan, Sh. Khlghatyan, A. A. Kocharyan and V. G. Gurzadyan Eur. Phys. J. Plus, 139 3 (2024) 246 Published online: 13 March 2024 DOI: 10.1140/epjp/s13360-024-05042-0