PentaQuark Mass and Structure

The Quark Delocalization, Color Screening Model has successfully reproduced the binding energy and structure of 9‐ and 12‐quark systems that are small nuclei, namely 3He and 4He, in a relativistic version. In a non‐relativistic version it has successfully been applied to 6‐quark systems to describe baryon‐baryon potentials, phase shifts and cross sections. It is applied here to KN molecular, Jaffe‐Wilczek, Karliner‐Lipkin and tetrahedral structures proposed for the reported pentaquark state, Θ+. In this model, we find that the excitation energy above KN threshold can be reproduced in some cases. The negative parity state is always found at a lower mass than the positive parity one. Concerns regarding additional physics effects which may obviate this result and a conjecture regarding two‐ vs. three‐body final state production of the Θ+ are also noted.