2006/06/30 by Dmitri Melikhov, Berthold Stech · 10 citations
Physics and Astronomy · #Diquark #Hadron #High-Energy Particle Collisions Research #Isospin #Meson #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Pseudoscalar #Quantum Chromodynamics and Particle Interactions #Quark #X(3872) #hep-ph
paper · pdf · doi:10.1103/physrevd.74.034022
published in Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields 74(3) (American Physical Society) · 19 pages, discussion of the parameters used is added on page 5, version published in Phys. Rev. D
openalex publication_date 2006/08/28 · arxiv created 2006/08/30 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We analyze fall-apart decays of polyquark (tetra, penta and molecule type) hadrons within the constituent quark picture. For processes in which a polyquark hadron goes to final states containing a light pseudoscalar meson the constraints given by chiral symmetry are implemented. As an application of the approach developed, fall-apart decays of a(980) and X(3872) are studied, assuming these mesons are polyquark hadrons. Two extreme options---confined diquark-diquark states and molecular states---are considered. For a0(980), the observed width can be obtained assuming that this meson is a diquark-diquark composite with a relatively large size of around 1\textdiv1.5 fm. The pure KK molecular-type state, however, can be excluded. For the X(3872), a sufficiently small width can be obtained if it is a dominantly isospin-0 diquark-diquark composite with a very large size of \ensuremath≥2.5 fm. The pure molecular option appears possible if the binding energy is tiny, Eb\ensuremath\lesssim0.2 MeV, corresponding to a huge size.