Extracting excited states from lattice QCD: the Roper resonance

Abstract

We present a new method for extracting excited states from a single two-point correlation function calculated on the lattice. Our method simply combines the correlation function evaluated at different time slices so as to ``subtract'' the leading exponential decay (ground state) and to give access to the first excited state. The method is applied to a quenched lattice study (volume = 24^3 x 64, beta = 6.2, 1/a = 2.55 GeV) of the first excited state of the nucleon using the local interpolating operator O = [uT C gamma5 d] u. The results are consistent with the identification of our extracted excited state with the Roper resonance N'(1440). The switching of the level ordering with respect to the negative-parity partner of the nucleon, N*(1535), is not seen at the simulated quark masses and, basing on crude extrapolations, is tentatively expected to occur close to the physical point.

arXiv commentversion to apper in Phys. Lett. B; additions in the presentation of the method; 3 references added; no change in the results and in the figures

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Cited by in corpus (29)

• Chiral Perturbation Theory and Baryon Properties
• Three particle quantization condition in a finite volume: 2. general formalism and the analysis of data
• Tuning for Three-flavors of Anisotropic Clover Fermions with Stout-link Smearing
• Three-particle quantization condition in a finite volume: 1. The role of the three-particle force
• Resonance properties from the finite-volume energy spectrum
• Excited hadrons on the lattice: Baryons
• Lattice QCD determination of patterns of excited baryon states
• Excited State Nucleon Spectrum with Two Flavors of Dynamical Fermions
• Hadron Spectroscopy with Dynamical Chirally Improved Fermions
• Spectral Analysis of Excited Nucleons in Lattice QCD with Maximum Entropy Method
• Excited-state spectroscopy of triply-bottom baryons from lattice QCD
• Pion momentum distributions in the nucleon in chiral effective theory
• Excited Baryon Spectroscopy from Lattice QCD: Finite Size Effect and Hyperfine Mass Splitting
• First Lattice QCD Study of the Sigma -> n Axial and Vector Form Factors with SU(3) Breaking Corrections
• First Lattice Study of the $N$-$P_{11}(1440)$ Transition Form Factors
• Gluonic excitation of non-exotic hybrid charmonium from lattice QCD
• Multiparticle States and the Hadron Spectrum on the Lattice
• Chiral corrections to the Roper mass
• Ordering of Spin-$\frac{1}{2}$ Excitations of the Nucleon in Lattice QCD
• Isolating the Roper Resonance in Lattice QCD
• Excited-State Effective Masses in Lattice QCD
• The mass of the Delta resonance in a finite volume: fourth-order calculation
• The Positive-Parity Baryon Spectrum and the Role of Hybrid Baryons
• The $\rho (1S,2S)$, $\psi (1S,2S)$, ${\rm Y}(1S,2S)$ and ${\psi }_t(1S,2S)$ mesons in a double pole QCD Sum Rule
• Masses of excited baryons from chirally improved quenched lattice QCD
• The Hadron Spectrum from Lattice QCD
• Two Nucleon-States in a Chiral Quark-Diquark Model
• Linear Algebra with Disordered Sparse Matrices that have Spatial Structure: Theory and Computation
• Baryons on the lattice