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Title: Meson and baryon spectrum for QCD with two light dynamical quarks

Abstract

We present results of meson and baryon spectroscopy using the Chirally Improved Dirac operator on lattices of size 16{sup 3}x32 with two mass-degenerate light sea quarks. Three ensembles with pion masses of 322(5), 470(4), and 525(7) MeV and lattice spacings close to 0.15 fm are investigated. Results for ground and excited states for several channels are given, including spin two mesons and hadrons with strange valence quarks. The analysis of the states is done with the variational method, including two kinds of Gaussian sources and derivative sources. We obtain several ground states fairly precisely and find radial excitations in various channels. Excited baryon results seem to suffer from finite size effects, in particular, at small pion masses. We discuss the possible appearance of scattering states, considering masses and eigenvectors. Partially quenched results in the scalar channel suggest the presence of a 2-particle state, however, in most channels we cannot identify them. Where available, we compare our results to results of quenched simulations using the same action.

Authors:
; ;  [1];  [1];  [2]
  1. Institut fuer Physik, FB Theoretische Physik, Universitaet Graz, A-8010 Graz (Austria)
  2. Institut fuer Theoretische Physik, Universitaet Regensburg, D-93040 Regensburg (Germany)
Publication Date:
OSTI Identifier:
21432881
Resource Type:
Journal Article
Journal Name:
Physical Review. D, Particles Fields
Additional Journal Information:
Journal Volume: 82; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.82.034505; (c) 2010 American Institute of Physics; Journal ID: ISSN 0556-2821
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BARYON SPECTROSCOPY; BARYONS; COMPARATIVE EVALUATIONS; DIRAC OPERATORS; EIGENVECTORS; EXCITATION; EXCITED STATES; GROUND STATES; MASS; MEV RANGE 100-1000; PIONS; QUANTUM CHROMODYNAMICS; QUARKS; SCATTERING; SIMULATION; SPECTRA; SPIN; VARIATIONAL METHODS; ANGULAR MOMENTUM; BOSONS; CALCULATION METHODS; ELEMENTARY PARTICLES; ENERGY LEVELS; ENERGY RANGE; ENERGY-LEVEL TRANSITIONS; EVALUATION; FERMIONS; FIELD THEORIES; HADRONS; MATHEMATICAL OPERATORS; MESONS; MEV RANGE; PARTICLE PROPERTIES; PSEUDOSCALAR MESONS; QUANTUM FIELD THEORY; QUANTUM OPERATORS; SPECTROSCOPY

Citation Formats

Engel, Georg P, Lang, C B, Limmer, Markus, Mohler, Daniel, TRIUMF, 4004 Wesbrook Mall Vancouver, BC V6T 2A3, and Schaefer, Andreas. Meson and baryon spectrum for QCD with two light dynamical quarks. United States: N. p., 2010. Web. doi:10.1103/PHYSREVD.82.034505.
Engel, Georg P, Lang, C B, Limmer, Markus, Mohler, Daniel, TRIUMF, 4004 Wesbrook Mall Vancouver, BC V6T 2A3, & Schaefer, Andreas. Meson and baryon spectrum for QCD with two light dynamical quarks. United States. https://doi.org/10.1103/PHYSREVD.82.034505
Engel, Georg P, Lang, C B, Limmer, Markus, Mohler, Daniel, TRIUMF, 4004 Wesbrook Mall Vancouver, BC V6T 2A3, and Schaefer, Andreas. Sun . "Meson and baryon spectrum for QCD with two light dynamical quarks". United States. https://doi.org/10.1103/PHYSREVD.82.034505.
@article{osti_21432881,
title = {Meson and baryon spectrum for QCD with two light dynamical quarks},
author = {Engel, Georg P and Lang, C B and Limmer, Markus and Mohler, Daniel and TRIUMF, 4004 Wesbrook Mall Vancouver, BC V6T 2A3 and Schaefer, Andreas},
abstractNote = {We present results of meson and baryon spectroscopy using the Chirally Improved Dirac operator on lattices of size 16{sup 3}x32 with two mass-degenerate light sea quarks. Three ensembles with pion masses of 322(5), 470(4), and 525(7) MeV and lattice spacings close to 0.15 fm are investigated. Results for ground and excited states for several channels are given, including spin two mesons and hadrons with strange valence quarks. The analysis of the states is done with the variational method, including two kinds of Gaussian sources and derivative sources. We obtain several ground states fairly precisely and find radial excitations in various channels. Excited baryon results seem to suffer from finite size effects, in particular, at small pion masses. We discuss the possible appearance of scattering states, considering masses and eigenvectors. Partially quenched results in the scalar channel suggest the presence of a 2-particle state, however, in most channels we cannot identify them. Where available, we compare our results to results of quenched simulations using the same action.},
doi = {10.1103/PHYSREVD.82.034505},
url = {https://www.osti.gov/biblio/21432881}, journal = {Physical Review. D, Particles Fields},
issn = {0556-2821},
number = 3,
volume = 82,
place = {United States},
year = {2010},
month = {8}
}