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arXiv · 2605.29975

A Fully Convolutional Approach to Denoising 2D Correlation Spectra

Nisar Nellikunnummel·Andi M Barbour·Lutz Wiegart·Tatiana Konstantinova·Anthony M DeGennaro
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Abstract

We present a fully convolutional denoising autoencoder (FC-DAE) tailored for two-dimensional representations of dynamic correlations that is applicable to many experimental techniques. Here, we demonstrate its performance on two-time intensity correlation functions ($C_2$) from X-ray photon correlation spectroscopy (XPCS). Unlike conventional denoising autoencoders that are typically restricted to fixed input sizes, the FC-DAE accepts inputs of arbitrary dimensions while preserving correlation structures across diverse dynamical regimes. The model is trained using experimentally derived $C_2$ data collected at NSLS-II beamlines, with data augmentation applied to expand the diversity of the dataset and reduce overfitting. The FC-DAE successfully recovers intricate dynamical features in low signal-to-noise conditions while maintaining structural fidelity. To assess reconstruction reliability, we employ quantitative metrics to evaluate structural fidelity and identify potential model-induced bias. Our results demonstrate that the FC-DAE provides robust denoising performance with high computational efficiency, enabling recovery of XPCS dynamics under photon-limited and low-dose measurement conditions.

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Nisar Nellikunnummel, Andi M Barbour, Lutz Wiegart, Tatiana Konstantinova, Anthony M DeGennaro. 2026-05-28. A Fully Convolutional Approach to Denoising 2D Correlation Spectra. https://arxiv.org/abs/2605.29975

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