Bayesian Model Selection for Electromagnetic Kaon Production on the Nucleon

TL;DR

This paper uses Bayesian analysis to evaluate a Regge model for K+ Lambda photoproduction, providing strong evidence for specific coupling constants and phase factors that traditional chi^2 methods could not determine.

Contribution

It introduces a Bayesian approach to model selection in electromagnetic kaon production, offering a more decisive evaluation of model parameters than conventional methods.

Findings

Bayesian evidence strongly favors a specific Regge model configuration.

Traditional chi^2 minimization could not reach the same conclusions.

The analysis identifies the sign and phase of coupling constants with high confidence.

Abstract

We present the results of a Bayesian analysis of a Regge model for K+ Lambda photoproduction. The model is based on the exchange of K+(494) and K*+(892) trajectories in the t-channel. For different prior widths, we find decisive Bayesian evidence (\Delta ln Z ~ 24) for a K+ Lambda photoproduction Regge model with a positive vector coupling and a negative tensor coupling constant for the K+(892) trajectory, and a rotating phase factor for both trajectories. Using the chi^2 minimization method, one could not draw this conclusion from the same dataset.