Angular Distributions, Polarization Observables, Spin Density Matrices and Statistical Tensors in Photoproduction of Two Pseudoscalar Mesons off a Nucleon

TL;DR

This paper derives general, model-independent formulas for decay distributions and polarization observables in two-meson photoproduction off nucleons, applicable to multiple resonances and interference effects.

Contribution

It provides a comprehensive framework to extract spin density matrices and statistical tensors of resonances in meson photoproduction, including interference effects.

Findings

Derived general expressions for decay distributions and polarization observables.

Formulas applicable to multiple resonances and interference effects.

Framework enables extraction of resonance properties from experimental data.

Abstract

In two meson photoproduction off a nucleon, for the case in which two of the three final state hadrons are products of the decay of an intermediate resonance, general expressions for its decay distribution and for polarization observables are derived in a model independent way. These are functions of either the spin density matrix elements (SDME's) or statistical tensors of the resonance, and the angles of its decay products. The expressions are general enough that it also describes cases where more than one resonance of arbitrary quantum numbers contributes, including interference effects. They can therefore be used to extract the SDME's or statistical tensors of the resonances that contribute to the reaction.