Irradiation of materials with short, intense ion pulses at NDCX-II

Abstract

We present an overview of the performance of the Neutralized Drift Compression Experiment-II (NDCX-II) accelerator at Berkeley Lab, and report on recent target experiments on beam driven melting and transmission ion energy loss measurements with nanosecond and millimeter-scale ion beam pulses and thin tin foils. Bunches with around 10 11 ions, 1-mm radius, and 2-30 ns FWHM duration have been created with corresponding fluences in the range of 0.1 to 0.7 J/cm 2 . To achieve these short pulse durations and mm-scale focal spot radii, the 1.1 MeV He + ion beam is neutralized in a drift compression section, which removes the space charge defocusing effect during final compression and focusing. The beam space charge and drift compression techniques resemble necessary beam conditions and manipulations in heavy ion inertial fusion accelerators. Quantitative comparison of detailed particle-in-cell simulations with the experiment play an important role in optimizing accelerator performance.

Acceleration of high charge ion beams with achromatic divergence by petawatt laser pulses

“…Each of the individual films of the layer records the deposited energy and the whole stack constitutes an energy resolved measurement. The dose response of the films and scanner unit was calibrated at the NDCX-II [35] facility with proton beams at 1.1 MeV. Reconstructed proton beam profiles are shown in Fig.…”

Absolute calibration of GafChromic film for very high flux laser driven ion beams

“…The calibration of HD-v2 films was performed at the Neutralized Drift Compression Experiment II (NDCX-II) particle accelerator at Lawrence Berkeley National Laboratory (LBNL). [23][24][25] NDCX-II can deliver short helium and now also proton pulses with a pulse duration of 2 to ∼10 ns (full-width at half-maximum, FWHM), as shown in Fig. 1.…”

Accelerator‐driven high‐energy‐density physics: Status and chances

“…Nagaoka University and Tokyo Institute of Technology, Japan, the University of Wisconsin, Michigan, and the Weizmann Institute, Israel, also participated in the light‐ion fusion research. The study of heavy/light ion beam transport and target physics used to be the main topic previously, and important results were obtained . Based on SESAME EoS models, Figure shows the expected bulk temperature of hydrogen, aluminium, and gold when they are irradiated with uranium ions of 400 MeV/u as a function of the beam intensity.…”