Structure of the Nucleon and its Excitations
arXiv:1711.05413 · doi:10.1051/epjconf/201817506019
Abstract
The structure of the ground state nucleon and its finite-volume excitations are examined from three different perspectives. Using new techniques to extract the relativistic components of the nucleon wave function, the node structure of both the upper and lower components of the nucleon wave function are illustrated. A non-trivial role for gluonic components is manifest. In the second approach, the parity-expanded variational analysis (PEVA) technique is utilised to isolate states at finite momenta, enabling a novel examination of the electric and magnetic form factors of nucleon excitations. Here the magnetic form factors of low-lying odd-parity nucleons are particularly interesting. Finally, the structure of the nucleon spectrum is examined in a Hamiltonian effective field theory analysis incorporating recent lattice-QCD determinations of low-lying two-particle scattering-state energies in the finite volume. The Roper resonance of Nature is observed to originate from multi-particle coupled-channel interactions while the first radial excitation of the nucleon sits much higher at approximately 1.9 GeV.
8 pages, 4 figures. Proceedings of the 35th International Symposium on Lattice Field Theory (Lattice 2017), 18 - 24 June 2017, Granada, Spain
References in corpus (11)
- Lattice QCD Evidence that the Lambda(1405) Resonance is an Antikaon-Nucleon Molecule
- Convergence of chiral effective field theory
- Isolating the Λ(1405) in Lattice QCD
- Hamiltonian effective field theory study of the resonance in lattice QCD
- Building the International Lattice Data Grid
- Roper Resonance in 2+1 Flavor QCD
- Wave Function of the Roper from Lattice QCD
- Magnetic moments of the low-lying {1/2}^- octet baryon resonances
- Discretisation Errors in Landau Gauge on the Lattice
- Magnetic dipole moment of the S11(1535) from the γp \to γηp reaction
- Magnetic Moments of Negative Parity Baryons from Effective Hamiltonian Approach to QCD