Quark Molecular Model of the S=0 Strange Pentaquark (u-sbar)-(uds) Baryon Spectrum

Abstract

We present a non-relativistic quark molecular model (QMM) of the strange crypto-exotic pentaquark baryon spectrum motivated by the recent data showing narrow, resonance enhancements in electromagnetic and hadronic production of kaons. Our model assumes color octet bonded quark molecular clusters forming exotic color singlet pentaquark baryons. We develop explicit molecular pentaquark wavefunctions that exhibit color interchange and cluster fermion antisymmetry. Our color electro-dynamics (CED) inspired Hamiltonian, which includes confinement, one gluon exchange and color magnetic interactions, is a natural generalization of the Isgur and Karl quark model Hamiltonian that reproduces the conventional meson (q-qbar) and baryon (qqq) spectrumWe introduce the idea of Color Magnetic Confinement (CMC) which is employed to restrict the physical pentaquark spectrum and constrain the fundamental constants (color gyromagnetic ratios) of the QMM-CED Hamiltonian. Comparing our QMM spectrum predictions with the recent experimental data in associated strangeness photo- and electro-production reactions, we identify 4 candidate states that have masses and total widths consistent with exotic pentaquark structure.