New constraints on heavy neutral leptons from Super-Kamiokande data P. Coloma, P. Hernández, V. Muñoz and I. M. Shoemaker Eur. Phys. J. C, 80 3 (2020) 235 Published online: 12 March 2020 DOI: 10.1140/epjc/s10052-020-7795-z