ACCELERATION OF A 2-DIMENSIONAL, 2-ENERGY GROUP NEUTRON NOISE SOLVER BASED ON A DISCRETE ORDINATES METHOD IN THE FREQUENCY DOMAINHuaiqian Yi, Paolo Vinai and Christophe DemazièreEPJ Web Conf., 247 (2021) 21005DOI: https://doi.org/10.1051/epjconf/202124721005