Article

A novel particle time of flight diagnostic for measurements of shock- and compression-bang times in D3He and DT implosions at the NIF

Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Review of Scientific Instruments (Impact Factor: 1.58). 07/2012; 83(10). DOI: 10.1063/1.4731000

ABSTRACT The particle-time-of-flight (pTOF) diagnostic, fielded alongside a wedge range-filter (WRF) proton spectrometer, will provide an absolute timing for the shock-burn weighted ρR measurements that will validate the modeling of implosion dynamics at the National Ignition Facility (NIF). In the first phase of the project, pTOF has recorded accurate bang times in cryogenic DT, DT exploding pusher, and D3He implosions using DD or DT neutrons with an accuracy better than ±70 ps. In the second phase of the project, a deflecting magnet will be incorporated into the pTOF design for simultaneous measurements of shock- and compression-bang times in D3He-filled surrogate implosions using D3He protons and DD-neutrons, respectively.

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