Search for low-lying lattice QCD eigenstates in the Roper regime

Abstract

The positive-parity nucleon spectrum is explored in $2+1$-flavour lattice QCD in a search for new low-lying energy eigenstates near the energy regime of the Roper resonance. In addition to conventional three-quark operators, we consider novel, local five-quark meson-baryon type interpolating fields that hold the promise to reveal new eigenstates that may have been missed in previous analyses. Drawing on phenomenological insight, five-quark operators based on $\sigma N$, $\pi N$ and $a_{0}N$ channels are constructed. Spectra are produced in a high-statistics analysis on the PACS-CS dynamical gauge-field configurations with $m_{\pi }=411\text{ MeV}$ via variational analyses of several operator combinations. Despite the introduction of qualitatively different interpolating fields, no new states are observed in the energy regime of the Roper resonance. This result provides further evidence that the low-lying finite-volume scattering states are not localised, and strengthens the interpretation of the Roper as a coupled-channel, dynamically-generated meson-baryon resonance.

7 Pages, 2 Figures

References in corpus (8)

• Lattice QCD Evidence that the Lambda(1405) Resonance is an Antikaon-Nucleon Molecule
• The Flavor Structure of the Excited Baryon Spectra from Lattice QCD
• Chiral dynamics of the S11(1535) and S11(1650) resonances revisited
• Structure of the $\mathbf{\Lambda }(1405)$ from Hamiltonian effective field theory
• Hamiltonian effective field theory study of the ${\mathbf{N}}^{\ast }(1440)$ resonance in lattice QCD
• Lattice baryon spectroscopy with multi-particle interpolators
• Isolating the Roper Resonance in Lattice QCD
• Ordering of Spin-$\frac{1}{2}$ Excitations of the Nucleon in Lattice QCD

Cited by in corpus (27)

• Pentaquark and Tetraquark states
• Scattering processes and resonances from lattice QCD
• Three-body Unitarity in the Finite Volume
• Finite-volume spectrum of ${\pi }^{+}{\pi }^{+}$ and ${\pi }^{+}{\pi }^{+}{\pi }^{+}$ systems
• Towards a theory of hadron resonances
• Three-body unitarity versus finite-volume ${\pi }^{+}{\pi }^{+}{\pi }^{+}$ spectrum from lattice QCD
• Charmed baryon spectrum from lattice QCD near the physical point
• The impact of ${\mathbf{K}}^{+}\mathbf{\Lambda }$ photoproduction on the resonance spectrum
• Structure of the Roper Resonance from Lattice QCD Constraints
• Electromagnetic Transition Form Factors of Baryon Resonances
• Chiral perturbation theory and nucleon-pion-state contaminations in lattice QCD
• Elastic Form Factors of Nucleon Excitations in Lattice QCD
• The Positive-Parity Baryon Spectrum and the Role of Hybrid Baryons
• Particle-dimer approach for the Roper resonance in a finite volume
• Roper State from Overlap Fermions
• Theoretical tools for neutrino scattering: interplay between lattice QCD, EFTs, nuclear physics, phenomenology, and neutrino event generators
• The Roper resonance: a genuine quark state or a dynamically generated structure?
• Role of chiral symmetry in the nucleon excitation spectrum
• Analysis of the data on spin density matrix elements for $\gamma p\to K^{\ast +}\Lambda$
• Analysis of the $\gamma n\to K^{+}{\Sigma }^{-}(1385)$ photoproduction
• A lattice QCD study of pion-nucleon scattering in the Roper channel
• Chiral Analysis of the Nucleon Mass and Sigma Commutator
• Dynamical generation of resonances in the P33 partial wave
• Combined analysis of the $\gamma n\to K^0{\Sigma }^0$ and $\gamma n\to K^{+}{\Sigma }^{-}$ reactions
• 3-body quantization condition in a unitary formalism
• Spectroscopy with Local Multi-hadron Interpolators in Lattice QCD
• Combined analysis of the data on cross sections and spin density matrix elements for $K^{\ast }\Sigma$ photoproduction reactions