Elementarity of composite systems

Abstract

The "compositeness" or "elementarity" is investigated for s-wave composite states dynamically generated by energy-dependent and independent interactions. The bare mass of the corresponding fictitious elementary particle in an equivalent Yukawa model is shown to be infinite, indicating that the wave function renormalization constant Z is equal to zero. The idea can be equally applied to both resonant and bound states. In a special case of zero-energy bound states, the condition Z = 0 does not necessarily mean that the elementary particle has the infinite bare mass. We also emphasize arbitrariness in the "elementarity" leading to multiple interpretations of a physical state, which can be either a pure composite state with Z = 0 or an elementary particle with Z \ne 0. The arbitrariness is unavoidable because the renormalization constant Z is not a physical observable.

13 pages, 8 figures, title changed, published

References in corpus (4)

• Observation of a resonance-like structure in the pi^+- psi' mass distribution in exclusive B-->K pi^+- psi' decays
• Origin of resonances in the chiral unitary approach
• Model for light scalars in QCD
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Cited by in corpus (5)

• Comprehensive analysis of the wave function of a hadronic resonance and its compositeness
• Structure of charmed baryons studied by pionic decays
• Two-body wave functions and compositeness from scattering amplitudes. I. General properties with schematic models
• $B_s\pi$--$B\bar{K}$ interactions in finite volume and the $X(5568)$
• Two-body Wave Functions, Compositeness, And The Internal Structure Of Dynamically Generated Resonances