以国内首个^(76)Ge同位素分离工程的离心级联检测控制为对象,通过DCS(Distributed Control System)控制系统硬件结构和组态编程,确保了主工艺关键设备——稳旋机的安全性,实现了实时查看现场各类工艺参数、远程开关电动阀、远程调节阀...以国内首个^(76)Ge同位素分离工程的离心级联检测控制为对象,通过DCS(Distributed Control System)控制系统硬件结构和组态编程,确保了主工艺关键设备——稳旋机的安全性,实现了实时查看现场各类工艺参数、远程开关电动阀、远程调节阀门开度及远程启停真空泵等功能,有力地保障了^(76)Ge同位素生产线的安全平稳运行。展开更多
为研究气体离心法分离^(72)Ge同位素的技术,以四氟化锗(GeF 4)为分离介质,通过理论计算,探索通过短级联浓缩法生产^(72)Ge的可能性。计算结果表明,使用相对丰度匹配级联(matched abundance ratio cascade,MARC)模型,两次分离后可以得到...为研究气体离心法分离^(72)Ge同位素的技术,以四氟化锗(GeF 4)为分离介质,通过理论计算,探索通过短级联浓缩法生产^(72)Ge的可能性。计算结果表明,使用相对丰度匹配级联(matched abundance ratio cascade,MARC)模型,两次分离后可以得到丰度高于55%的^(72)Ge。在实验室现有的离心级联上,采用21级阶梯级联的结构,通过调整级联内部工况和外参量,对级联分离性能进行优化。经过两次分离实验后,最终得到^(72)Ge丰度高于60%的产品。展开更多
We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of^(76)Ge.A...We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of^(76)Ge.A total of 504.3 kg⋅day effective exposure data was accumulated.The anti-coincidence and the multi/single-site event(MSE/SSE)discrimination methods were used to suppress the background in the energy region of interest(ROI,1989–2089 keV for this work)with a factor of 23.A background level of 0.33 counts/(keV⋅kg⋅yr)was realized.The lower limit on the half life of^(76)Ge 0νββdecay was constrained as T_(1/2)^(0ν)>1.0×10^(23)yr(90%C.L.),corresponding to the upper limits on the effective Majorana neutrino mass:<mββ><3.2–7.5 eV.展开更多
文摘以国内首个^(76)Ge同位素分离工程的离心级联检测控制为对象,通过DCS(Distributed Control System)控制系统硬件结构和组态编程,确保了主工艺关键设备——稳旋机的安全性,实现了实时查看现场各类工艺参数、远程开关电动阀、远程调节阀门开度及远程启停真空泵等功能,有力地保障了^(76)Ge同位素生产线的安全平稳运行。
文摘为研究气体离心法分离^(72)Ge同位素的技术,以四氟化锗(GeF 4)为分离介质,通过理论计算,探索通过短级联浓缩法生产^(72)Ge的可能性。计算结果表明,使用相对丰度匹配级联(matched abundance ratio cascade,MARC)模型,两次分离后可以得到丰度高于55%的^(72)Ge。在实验室现有的离心级联上,采用21级阶梯级联的结构,通过调整级联内部工况和外参量,对级联分离性能进行优化。经过两次分离实验后,最终得到^(72)Ge丰度高于60%的产品。
基金Supported by the National Key Research and Development Program of China(2017YFA0402201,2022YFA1604701,2022YFA1605000)the National Natural Science Foundation of China(12322511,12175112,12005111,11725522)。
文摘We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of^(76)Ge.A total of 504.3 kg⋅day effective exposure data was accumulated.The anti-coincidence and the multi/single-site event(MSE/SSE)discrimination methods were used to suppress the background in the energy region of interest(ROI,1989–2089 keV for this work)with a factor of 23.A background level of 0.33 counts/(keV⋅kg⋅yr)was realized.The lower limit on the half life of^(76)Ge 0νββdecay was constrained as T_(1/2)^(0ν)>1.0×10^(23)yr(90%C.L.),corresponding to the upper limits on the effective Majorana neutrino mass:<mββ><3.2–7.5 eV.
