A search for new light charged particles in photoproductionV.I. Alekseev, V.A. Baskov, V.A. Dronov, Yu.F. Krechetov, A.I. L’vov, L.N. Pavlyuchenko, V.V. Polyanskiy and S.S. SidorinEPJ Web Conf., 204 (2019) 08009DOI: https://doi.org/10.1051/epjconf/201920408009