New developments in model-independent Partial-Wave Analysis

TL;DR

This paper explores advanced model-independent partial-wave analysis methods for resonance studies, systematically testing different fit models on pseudo data to identify their capabilities and limitations.

Contribution

It introduces extended approaches that overcome previous restrictions to subsets of partial waves and uncovers hidden caveats in earlier methods.

Findings

Suitable methods exist for full partial-wave freedom

Mathematical description impacts analysis results

Hidden caveats in previous approaches are revealed

Abstract

Partial-wave analyses (PWA) are an essential tool for studying resonance structures in decays with hadronic multi-body final states. For several years, more model-independent approaches to such analyses have been used for various decay final states. However, up to now, these methods have mostly been applied to sub-sets of partial waves, also called freed waves. In this article, we explore possibilities and limitations of extended model-independent approaches. We systematically apply various different fit models to the analysis of pseudo data sets, to study both the impact of the mathematical description used for the freed waves and the choice of simultaneously freed waves. We can show that suitable methods exist, which lift restrictions to only sub-sets of freed partial waves and demonstrate hidden caveats present in previous works.