Ceramic samples of cerium-doped yttrium aluminum garnet (YAG:Ce) were successfully synthesized utilizing a high-powered electron flux field with a considerable energy level of 1.4 MeV and a power density of 23 kW/cm2. The ceramics were formed in a remarkable time span of just one second from a specifically prepared mix of yttrium, aluminum, and cerium oxides. The process of radiation-assisted synthesis of ceramics within radiation flux fields fundamentally deviates from the methodologies commonly employed today. Analyzed diffraction patterns closely align with those documented for YAG:Ce crystals, both in peak position and proportion. Furthermore, every sample consistently demonstrated a space group symmetry of Ia-3d. The luminescence and excitation spectra of ceramics synthesized in this study closely resemble those of YAG:Ce ceramics produced by other methods and YAG:Ce -based phosphors. The luminescence bands exhibit high efficiency, and the intensity ratios of the UV bands vary among the studied phosphors. The ceramics' radiation-to-luminescence conversion efficiency was found to be impressive, achieving scores of 0.57 and 0.48 in the industrial phosphors SDL 4000 and YAG-02, respectively. It was also observed that an increase in quantum efficiency of the samples could be achieved via high-temperature annealing. High conversion efficiency underscores the potential of the outlined luminescent ceramics synthesis method.