A Low Cost, Sub-Picosecond Transition Radiation Based Gamma Ray Detector

Tremendous cost and technical effort go into achieving state-of-the-art temporal resolution (~10 ps) on gamma ray detectors used on inertial confinement fusion facilities. This resolution has given novel insights into the detailed evolution of fusion hot spot evolution, however, in the near future even ~10 ps will not be fast enough for resolving complex structure and the timescales of burn in robust ignition and Double Shell implosions. Techniques used in free electron lasers utilizing coherent transition radiation and sub-THz radiation measurement techniques can be leveraged to create a novel gamma ray detector that can achieve sub-picosecond resolution with massively reduced complexity and cost. This presentation will outline the concept and initial design for a newly funded LANL project to investigate a coherent transition radiation-based gamma ray history detector for use on OMEGA, NIF, and next generation ICF facilities.

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