Characterization of external 3He ion beams used for ex-vacuo nuclear reaction analysis of deuterium

doi:10.1016/0168-583X(90)90836-J

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms

Volume 45, Issues 1–4, 2 January 1990, Pages 285-289

https://doi.org/10.1016/0168-583X(90)90836-J Get rights and content

Abstract

In-air D(³He, p)⁴He nuclear reaction analysis (NRA) using external ³He ion beams is now routinely used to characterize deuterium in both fusion and fission reactor materials. The depth resolution, lateral resolution, and detection sensitivity attainable in these ex-vacuo analyses is influenced by the energy spread, the spatial divergence, and the nuclear reaction background produced by extraction of the ³He ion beam through a suitable exit window foil and subsequent transmission of the beam through one or more millimeters of air to the target. In the present paper, the energy and spatial distributions of ex-vacuo MeV ³He ion beams are measured for transmission distances in air of 0 to 15 mm. Exit windows made from both commercially produced foils (3.81 μm thick Au/Al) and foils prepared in the laboratory (1.14 μm thick Au/Al) by e-beam evaporation onto NaCl have been examined. The measured distributions are compared to TRIM simulations, and the resolution of in-air D(³He, p)⁴He NRA is assessed. Finally, interfering background nuclear reaction yields in air are measured as a function of ex-vacuo ³He beam energy, and the resulting deuterium detection sensitivity is discussed.

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Characterization of external 3He ion beams used for ex-vacuo nuclear reaction analysis of deuterium

Abstract

Nucl. Instr. and Meth.

Nucl. Instr. and Meth.

Nucl. Instr. and Meth.

Characterization of external ³He ion beams used for ex-vacuo nuclear reaction analysis of deuterium