LBNL, Berkeley, California, USA
The Neutralized Drift Compression Experiment (NDCX-II) is a new induction accelerator facility designed to facilitate user experiments in high energy density laboratory physics, intense beam physics, and materials processing and testing with intense, pulsed ion beams. The facility has completed the initial commissioning phase of its injector, 27-cell solenoid transport lattice, induction accelerator modules and non-neutral pulse compression section. Space-charge-dominated Li+ beams carrying 20-50 nC have been generated from the 133 kV pulsed, ~1.0 microsecond (FWHM), 65-mA injector, and compressed to 20-30 ns with 0.75-1.3 A peak currents and amplification factors of 10-20. We report results of non- neutral beam compression and transport studies to generate variable ion beam fluences on to solid targets. We also report on studies of dose rate effects in pulsed ion implantation and on the recombination dynamics of radiation induced defects in semiconductors using the NDCX-II Li+ beam.
WEOAA1
LBNL, Berkeley, California, USA
SLAC, Menlo Park, California, USA
JLAB, Newport News, Virginia, USA
Fermilab, Batavia, USA
We present an overview of design studies and R&D toward NGLS a Next Generation Light Source initiative at LBNL. The design concept is based on a multi-beamline soft x-ray FEL array powered by a CW superconducting linear accelerator, and operating with a high bunch repetition rate of approximately 1 MHz. The linac design uses TESLA and ILC technology, supplied by an injector based on a CW normal-conducting VHF photocathode electron gun. Electron bunches from the linac are distributed by RF deflecting cavities to the array of independently configurable FEL beamlines with nominal bunch rates of ~100 kHz in each FEL, with uniform pulse spacing, and some FELs capable of operating at the full linac bunch rate. Individual FELs may be configured for different modes of operation, including self-seeded and external-laser-seeded, and each may produce high peak and average brightness x-rays with a flexible pulse format.
WEOBB2
LBNL, Berkeley, California, USA
Associate particle imaging (API) is an active interrogation method for neutron based imaging of materials. Energetic alpha particles are emitted in kinematic correlation with neutrons in DT fusion reactions, forming a virtual neutron beam. When alphas are detected in a position sensitive detector and their arrival time is also recorded then time tagged neutrons can be used for 3D imaging e. g. of concealed objects in a transmission geometry or through detection of a prompt gamma ray. The imaging resolution in API systems is often limited by the area from which neutron originate. This area is determined by the spot size of a mixed D+ and T+ ion beam. We have adapted microwave driven ion sources (permanent magnets, 2.45 GHz) for the efficient production of hydrogen ions (all isotopes) with high current density (50 to 100 mA/cm2) and high fractions of atomic ions [1]. The high current density allows us to extract ions with small apertures and form beam spots on the neutron production target of less than 1 mm in diameter. In our presentation we will describe the API principle and report our results on the development of an API system with high spatial resolution.
[1] Q. Ji, AIP Conf. Proc. Vol 1336, 528-532 (2011).