Testing the scalar sector of the standard-model extension with neutron gravity experiments C. A. Escobar, A. Martín-Ruiz, A. M. Escobar-Ruiz and Román Linares Eur. Phys. J. Plus, 137 10 (2022) 1186 Published online: 27 October 2022 DOI: 10.1140/epjp/s13360-022-03412-0