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arXiv · 2406.00311

Error evaluation of partial scattering functions obtained from contrast variation small-angle neutron scattering

Koichi Mayumi·Tatsuro Oda·Shinya Miyajima·Ippei Obayashi·Kazuaki Tanaka
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Abstract

Contrast variation small-angle neutron scattering (CV-SANS) is a powerful tool to evaluate the structure of multi-component systems by decomposing scattering intensities $I$ measured with different scattering contrasts into partial scattering functions $S$ of self- and cross-correlations between components. The measured $I$ contains a measurement error, $\Delta I$, and $\Delta I$ results in an uncertainty of partial scattering functions, $\Delta S$. However, the error propagation from $\Delta I$ to $\Delta S$ has not been quantitatively clarified. In this work, we have established deterministic and statistical approaches to determine $\Delta S$ from $\Delta I$. We have applied the two methods to (i) computational data of a core-shell sphere and experimental CV-SANS data of (ii) clay/polyethylene glycol (PEG) aqueous solutions and (iii) polyrotaxane solutions, and have successfully estimated the errors of \(S\). The quantitative error estimation of \(S\) offers us a strategy to optimize the combination of scattering contrasts to minimize error propagation.

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Koichi Mayumi, Tatsuro Oda, Shinya Miyajima, Ippei Obayashi, Kazuaki Tanaka. 2024-06-01. Error evaluation of partial scattering functions obtained from contrast variation small-angle neutron scattering. https://arxiv.org/abs/2406.00311

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