Developing a high-intensity laser-plasma experimental capability for the Pair Plasma Discovery Science campaign on NIF-ARC
ORAL
Abstract
The Advanced Radiographic Capability (ARC) laser at the NIF produces high-energy pulses (up to 4 kJ) but has a large focal spot with sub-relativistic intensities (1e18 W/cm2) below that needed for applications such as radiography, and pair creation. Results from the first high-intensity shots on ARC demonstrated a surprisingly high electron temperature of 2.2 MeV [1]. 2D PIC simulations show a dephasing acceleration mechanism where electrons sample a large area of changing laser phase, only achievable using long pulse durations with large spatial scales. The electron temperature was then increased by using parabolic focusing plasma optics [2] where inferred intensity was an order of magnitude compared to a flat target. This enabled the observation of pairs on ARC for the first time [3]. This newly developed high-intensity platform benefits a range of short-pulse, high-intensity laser applications at NIF.
*This work was performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract DE-AC52- 07NA27344 and funded by the LLNL LDRD program under tracking code 17-ERD-010 and 19-SI-002.
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