Development of Neutron Streak Camera Using Recoil Protons

利用反冲质子开发中子条纹相机

• 批准号: 06558064
• 负责人: MIYANAGA Noriaki
• 金额: $ 7.23万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06558064/
• 关键词: Neutron; Streak camera; Recoil proton; Inertial confinement fusion; Dense plasma; 高速応答

For the application to the diagnostics of inertial confinement fusion plasma, we have developed a new type of streak camera which uses recoil protons in a plastic cathode. The distinctive characteristics and performances are as follows ;1) We calculated the detection efficiency for 14.1-MeV (D-T) neutrons. This calculation is based on the Monte-Carlo code which treats the energy slowing-down of protons in the plastic cathode. The differential cross section of neutron scattering by hydrogen and the angular-dependent energy of recoil protons are also taken into account. The detection efficiency increases with increasing the cathode thickness, then saturates to an asymptotic value at the thickness exceeding the range (2.2mm) of forward scattered proton. The maximum detection efficiency was inferred to be 0.4%.2) The time-of-flight spread of neutrons and recoil protons causes the degradation of time resolution. The time spread of the emission of secondary electrons saturates to be about 5ps at the cathode thickness of 2.2mm.3) We have constructed a detection system which has a streak tube of 25-mm cathode diameter. This streak camera was examined using an ultraviolet short pulse laser. The measured time resolution is better than 12ps at a sweep speed of 26mm/ns on the output phosphor screen.4) The time resolution of this neutron streak camera was estimated to be 14-19ps for the typical width (100-300mum) of cathode slit.5) This neutron streak camera can be applicable to the laser fusion experiments if the total neutron yield is (3.5-7) *10^9.

为了应用于惯性约束聚变等离子体的诊断，我们开发了一种新型条纹相机，它在塑料阴极中使用反冲质子。其独特的特征和性能如下；1）我们计算了14.1-MeV（D-T）中子的探测效率。该计算基于蒙特卡罗代码，该代码处理塑料阴极中质子的能量减慢。氢散射的微分截面和反冲质子的角度相关能量也被考虑在内。检测效率随着阴极厚度的增加而增加，然后在厚度超过前向散射质子范围（2.2mm）时达到渐近值。推断最大探测效率为0.4%。2)中子和反冲质子的飞行时间扩展导致时间分辨率下降。当阴极厚度为2.2mm时，二次电子发射的时间扩展饱和至约5ps。3)我们构建了一个具有25mm阴极直径的条纹管的检测系统。使用紫外短脉冲激光检查该条纹相机。在输出荧光屏上扫描速度为26mm/ns时，测得的时间分辨率优于12ps。4)对于典型的阴极狭缝宽度(100-300mum)，该中子条纹相机的时间分辨率估计为14-19ps。5)如果总中子产额为(3.5-7)*10^9，则该中子条纹相机可适用于激光聚变实验。