An ADS 650 MHz medium beta cavity study and designLIU Zhen-Chao( ) GAO Jie( ) LI Zhong-Quan( ) ZHAI Ji-Yuan( ) ZHAO Tong-Xian( ) LI Da-Zhang( ) LIU Yi-Lin( ) SUN Yi( )

The full-potential linear augmented plane wave method based on density functional theory is employed to investigate the electronic structure of BaSi 2 . With the constant relaxation time and rigid band approximation, the electrical conductivity, Seebeck coefficient and figure of merit are calculated by using Boltzmann transport theory, further evaluated as a function of carrier concentration. We find that the Seebeck coefficient is more anisotropic than electrical conductivity. The figure of merit of BaSi 2 is predicted to be quite high at room temperature, implying that optimal doping may be an effective way to improve thermoelectric properties.

Zhenghui (米正辉) 1;2;1) SUN Yi(孙毅) 2 PAN Weimin(潘卫民) 2 LIN Haiying(林海英) 2 ZHAO Danyang (赵丹阳) 1;2 LU Xiangyang(鲁向阳) 3 QUAN Shengwen(全胜文) 3 LUO Xing(罗星) 3 LI Ming(黎明) 4,5 YANG Xingfan(杨兴繁) 4,5 WANG Guangwei(王光伟) 2 DAI Jianping(戴建枰) 2 LI Zhongquan(李中泉) 2 MA Qiang(马强) 2 SHA Peng(沙鹏)

The simulation and analysis for electron multipacting phenomenon in low β spoke superconducting cavity in ADS proton accelerator are proposed. Using both CST and Track3P codes, the electron multipacting calculation for β = 0.12 spoke superconducting cavity is implemented. The methods of multipacting calculation on both codes are studied and described. With the comparison between the calculation results and the cavity vertical test result, the accuracy and reliability of different code on calculating multipacting are analyzed. Multipacting calculation can help to understand the result of vertical test and also can help to do the optimation in cavity design.