Improving $Λ$ Signal Extraction with Domain Adaptation via Normalizing Flows
This work addresses domain mismatch issues in particle physics signal extraction, but it is incremental as it builds on existing classifier methods.
The study tackled the problem of improving Λ hyperon signal extraction at CLAS12 by using normalizing flows for domain adaptation between Monte Carlo simulation and data, resulting in a broader range where classifier cuts yield similar performance metrics.
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 $Λ$ Hyperons at CLAS12. Normalizing Flows can help model complex probability density functions that describe physics processes, enabling uses such as event generation. $Λ$ 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.