Aeroacoustic source characterization at fan test facility with spherical harmonics of the half-space - Vourakis, Michail; Zotter, Franz; Brandão, Eric; Zea, Elias (eFläktar, grundförutsättning för eMobilitet II Jasa Express Letters Aeroacoustic source characterization at fan test facility with spherical harmonics of the half-space, 2025)