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arXiv · 1211.6385

Towards pump-probe experiments of defect dynamics with short ion beam pulses

T. Schenkel·S. M. Lidia·C. D. Weis·W. L. Waldron·J. Schwartz·A. M. Minor·P. Hosemann·J. W. Kwan
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Abstract

A novel, induction type linear accelerator, the Neutralized Drift Compression eXperiment (NDCX-II), is currently being commissioned at Berkeley Lab. This accelerator is designed to deliver intense (up to 3x1011 ions/pulse), 0.6 to ~600 ns duration pulses of 0.13 to 1.2 MeV lithium ions at a rate of about 2 pulses per minute onto 1 to 10 mm scale target areas. When focused to mm-diameter spots, the beam is predicted to volumetrically heat micrometer thick foils to temperatures of ~30,000 K. At lower beam power densities, the short excitation pulse with tunable intensity and time profile enables pump-probe type studies of defect dynamics in a broad range of materials. We briefly describe the accelerator concept and design, present results from beam pulse shaping experiments and discuss examples of pump-probe type studies of defect dynamics following irradiation of materials with intense, short ion beam pulses from NDCX-II.

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T. Schenkel, S. M. Lidia, C. D. Weis, W. L. Waldron, J. Schwartz, A. M. Minor, P. Hosemann, J. W. Kwan. 2012-11-27. Towards pump-probe experiments of defect dynamics with short ion beam pulses. https://doi.org/10.1016/j.nimb.2013.05.074

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