Investigation of energy deposition and irradiation non-uniformity of lead heavy ion beam in two different target structures

By using the OK1 code with some corrections, the energy deposition profile and irradiation non-uniformity of lead (Pb) beams are studied onto a direct-drive fuel pellet, in mono-layer diamond pellet structure and an aluminum mono-layer pellet structure using 12- beams and 120- beams irradiation schemes. The root-mean-square (RMS) non-uniformity value becomes ?RMS= 5.70 %, 4.46% in a diamond mono-layer pellet structure and ?RMS= 10.72 %, 6.94% in an aluminum mono-layer pellet structure for the 12-beams and 120-beams system, respectively. The maxiumum of deposited energy value is 6.9960×104 J in diamond mono-layer pellet structure and this value is 5.1393×104J in an aluminum mono-layer pellet structure in the 3.89 mm of pellet radius for the 12-beams systems. As a result, the RMS and PTV non-uniformities are decreased with increasing of the total beam numbers and these values are low at the Bragg peak layer. The RMS non-uniformity for diamond mono-layer pellet structure was lower than that for aluminum mono-layer pellet structure.