Calibration of a neutron time-of-flight detector with a rapid instrument response function for measurements of bulk fluid motion on OMEGA.
Calibration of a neutron time-of-flight detector with a rapid instrument response function for measurements of bulk fluid motion on OMEGA.
复制标题
校准具有快速仪器响应功能的中子飞行时间探测器，用于测量 OMEGA 上的整体流体运动。
DOI：
10.1063/1.5037324
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
M. G. Johnson
中科院分区：
文献类型：
--
作者：
O. Mannion;V. Glebov;C. Forrest;J. Knauer;V. Goncharov;S. Regan;T. Sangster;C. Stoeckl;M. G. Johnson
一种新开发的具有快速仪器响应功能的中子飞行时间（nTOF）诊断仪已在高度准直的瞄准线上安装在OMEGA激光器上。通过使用一个小的塑料闪烁体的体积，探测器提供了一个狭窄的仪器响应的1.7 ns的半高全宽，同时保持一个大的信号-噪声比的中子产额之间的1010和1014。OMEGA硬件定时系统与光学基准沿着使用，以提供绝对nTOF测量，精确度为1.56 ps。快速的仪器响应使得能够精确测量初级氘-氚中子峰形，而光学基准允许绝对中子能量测量。新探测器测量中子平均能量的不确定性为1.7keV，对应于热点速度投影的不确定性为1.12km/s。通过中子能谱的测量，给出了低温靶中流体运动的证据。
A newly developed neutron time-of-flight (nTOF) diagnostic with a fast instrument response function has been fielded on the OMEGA laser in a highly collimated line of sight. By using a small plastic scintillator volume, the detector provides a narrow instrument response of 1.7 ns full width at half maximum while maintaining a large signal-to-noise ratio for neutron yields between 1010 and 1014. The OMEGA hardware timing system is used along with an optical fiducial to provide an absolute nTOF measurement to an accuracy of ∼56 ps. The fast instrument response enables the accurate measurement of the primary deuterium-tritium neutron peak shape, while the optical fiducial allows for an absolute neutron energy measurement. The new detector measures the neutron mean energy with an uncertainty of ∼7 keV, corresponding to a hot-spot velocity projection uncertainty of ∼12 km/s. Evidence of bulk fluid motion in cryogenic targets is presented with measurements of the neutron energy spectrum.