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arXiv · 1605.02526

Absolute hydrogen depth profiling using the resonant $^{1}$H($^{15}$N,$αγ$)$^{12}$C nuclear reaction

Tobias P. Reinhardt·Shavkat Akhmadaliev·Daniel Bemmerer·Klaus Stöckel·Louis Wagner
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Abstract

Resonant nuclear reactions are a powerful tool for the determination of the amount and profile of hydrogen in thin layers of material. Usually, this tool requires the use of a standard of well-known composition. The present work, by contrast, deals with standard-less hydrogen depth profiling. This approach requires precise nuclear data, e.g. on the widely used $^{1}$H($^{15}$N,$αγ$)$^{12}$C reaction, resonant at 6.4\,MeV $^{15}$N beam energy. Here, the strongly anisotropic angular distribution of the emitted $γ$-rays from this resonance has been re-measured, resolving a previous discrepancy. Coefficients of (0.38$\pm$0.04) and (0.80$\pm$0.04) have been deduced for the second and fourth order Legendre polynomials, respectively. In addition, the resonance strength has been re-evaluated to (25.0$\pm$1.5)\,eV, 10\% higher than previously reported. A simple working formula for the hydrogen concentration is given for cases with known $γ$-ray detection efficiency. Finally, the absolute approach is illustrated using two examples.

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Tobias P. Reinhardt, Shavkat Akhmadaliev, Daniel Bemmerer, Klaus Stöckel, Louis Wagner. 2016-05-09. Absolute hydrogen depth profiling using the resonant $^{1}$H($^{15}$N,$αγ$)$^{12}$C nuclear reaction. https://doi.org/10.1016/j.nimb.2016.05.009

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