Are there S=-2 Pentaquarks?

TL;DR

This paper critically examines recent claims of S=-2 pentaquark evidence, comparing them with extensive existing data, and finds inconsistencies that challenge the validity of the claimed signals.

Contribution

It provides a critical analysis of recent pentaquark claims, highlighting inconsistencies with established Xi spectroscopy data and examining additional exotic channels.

Findings

Claims are partially inconsistent with existing Xi spectroscopy data.

Additional exotic channels show internal inconsistencies with purported signals.

The analysis questions the validity of the claimed S=-2 pentaquark evidence.

Abstract

Recent evidence for pentaquark baryons in the channels $\Xi^-\pi^-$, $\Xi^-\pi^+$ and their anti-particles claimed by the NA49 collaboration is critically confronted with the vast amount of existing data on $\Xi$ spectroscopy which was accumulated over the past decades. It is shown that the claim is at least partially inconsistent with these data. In addition two further exotic channels of the pentaquark type available in the NA49 data are investigated. It is argued that this study leads to internal inconsistency with the purported signals.