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arXiv · 2403.14076

Improving $\Lambda$ Signal Extraction with Domain Adaptation via Normalizing Flows

Abstract

The present study presents a novel application for normalizing flows for domain adaptation. The study investigates the ability of flow based neural networks to improve signal extraction of $\Lambda$ Hyperons at CLAS12. Normalizing Flows can help model complex probability density functions that describe physics processes, enabling uses such as event generation. $\Lambda$ signal extraction has been improved through the use of classifier networks, but differences in simulation and data domains limit classifier performance; this study utilizes the flows for domain adaptation between Monte Carlo simulation and data. We were successful in training a flow network to transform between the latent physics space and a normal distribution. We also found that applying the flows lessened the dependence of the figure of merit on the cut on the classifier output, meaning that there was a broader range where the cut results in a similar figure of merit.

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Rowan Kelleher, Matthew McEneaney, Anselm Vossen. 2024-03-21. Improving $\Lambda$ Signal Extraction with Domain Adaptation via Normalizing Flows. https://arxiv.org/abs/2403.14076

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