The Dynamical Diquark Model: First Numerical Results

Abstract

We produce the first numerical predictions of the dynamical diquark model of multiquark exotic hadrons. Using Born-Oppenheimer potentials calculated numerically on the lattice, we solve coupled and uncoupled systems of Schroedinger equations to obtain mass eigenvalues for multiplets of states that are, at this stage, degenerate in spin and isospin. Assuming reasonable values for these fine-structure splittings, we obtain a series of bands of exotic states with a common parity eigenvalue that agree well with the experimentally observed charmoniumlike states, and we predict a number of other unobserved states. In particular, the most suitable fit to known pentaquark states predicts states below the charmonium-plus-nucleon threshold. Finally, we examine the strictest form of Born-Oppenheimer decay selection rules for exotics and, finding them to fail badly, we propose a resolution by relaxing the constraint that exotics must occur as heavy-quark spin-symmetry eigenstates.

27 pages, 1 PDF figure. Version accepted by JHEP. Includes new results and discussion reflecting the recent LHCb pentaquark discoveries

References in corpus (8)

• Multiquark Resonances
• Exotics: Heavy Pentaquarks and Tetraquarks
• The Z(4430) and a New Paradigm for Spin Interactions in Tetraquarks
• A New Picture for the Formation and Decay of the Exotic $XYZ$ Mesons
• Employing spin symmetry to disentangle different models for the XYZ states
• Could the $X(3915)$ and the $X(3930)$ Be the Same Tensor State?
• The Dynamical Diquark Model: First Numerical Results
• Spectroscopy of Exotic Hadrons Formed from Dynamical Diquarks

Cited by in corpus (2)

• The Dynamical Diquark Model: First Numerical Results
• The Hydrogen Bond of QCD