Response Of A CVD Diamond Detector To ''Typical'' Deuterium-Tritium NIF Implosions For Areal Density Measurement

Dauffy, L S ; Lerche, R A ; Phillips, T W

Lawrence Livermore National Laboratory

关键词: Saturation;    Spectra;    Amplitudes;    Neutrons;    36 Materials Science;   

DOI  :  10.2172/15016014
RP-ID  :  UCRL-TR-211523
RP-ID  :  W-7405-ENG-48
RP-ID  :  15016014

美国|英语

来源: UNT Digital Library

【 摘 要 】

CVD diamond detector signals from Deuterium-Tritium implosions have been simulated in order to study the feasibility of measuring areal density using the ratio of downscattered to primary neutrons during the ignition campaign at the NIF. Simulated neutron spectra for three ''typical'' DT implosions were weighted with the CVD diamond sensitivity to obtain an estimated signal at several distances from the target chamber center. The 14 MeV peak was found to have an amplitude about three orders of magnitude larger than the down-scattered signal for the three spectra. At a target to detector distance of 17 m (just outside the target bay wall) and for a 1 cm{sup 2} wafer, signals are large enough to be recorded, well above any background and electronic noise. The uncertainty in the areal density measurement comes mainly from the uncertainty in the CVD diamond energy dependent sensitivity, the accuracy of the background simulation, and the effect of the saturation of both detector and electronics after the large 14 MeV peak. Nevertheless, the results found in this study are encouraging, and the remaining sources of uncertainty should now be addressed.