Observable gravitational waves from hyperkination in Palatini gravity and beyond Samuel Sánchez López, Konstantinos Dimopoulos, Alexandros Karam and Eemeli Tomberg Eur. Phys. J. C, 83 12 (2023) 1152 Published online: 19 December 2023 DOI: 10.1140/epjc/s10052-023-12332-x