Application of the single-channel, single-energy AA/PWA method to $K^{+} \Lambda$ photoproduction

TL;DR

This paper applies a novel single-channel, single-energy partial wave analysis method, AA/PWA, to $K^{+} \Lambda$ photoproduction, confirming its advantages and comparing results with previous analyses, but questioning some resonance interpretations.

Contribution

The paper demonstrates the application of the AA/PWA method to $K^{+} \Lambda$ photoproduction, confirming its benefits and providing a detailed comparison with existing analyses.

Findings

Confirmed the size and shape of Bonn-Gatchina multipoles.

Did not confirm the $N(1880) rac{1}{2}^{+}$ resonance interpretation.

Emphasized the importance of data self-consistency.

Abstract

The new single-channel, single-energy partial wave analysis method based on a simultaneous use of amplitude and partial wave analysis called AA/PWA, developed and tested on $\eta$ photoproduction in ref. Svarc et al, PRC 102, 064609 (2020), is applied to the $K^{+} \Lambda$ photoproduction for the center-of-mass energy range of 1625 MeV $< W <$ 2296 MeV. A complete set of multipoles has been created. The advantages of the method have been confirmed, and a comparison with the only existing single-energy partial wave analysis of $K^{+} \Lambda$ photoproduction given in refs. Anisovich et al PRL 119 062004 (2017) and Anisovich et al Eur. Phys. J. A 53: 242 (2017) is presented. We confirm the size and shape of Bonn-Gatchina multipoles, but we do not confirm the unambiguous interpretation of the structure in the $M_{1-}$ multipole as a $N(1880) \frac{1}{2}^{+}$ resonance. The decisive role of the self-consistency of the world database is emphasized.