Towards a Determination of the Spectrum of QCD Using a Space-Time Lattice.

Juge, K. J. ; Lichtl, A. ; Morningstar, C. ; Edwards, R. G. ; Richards, D. G.

Technical Information Center Oak Ridge Tennessee

关键词: Quantum chromodynamics;    Energy levels;    Mesons;    Space-time;    Symmetry;   

RP-ID  :  DE2006876007

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Progress by the Lattice Hadron Physics Collaboration in determining the baryon and meson resonance spectrum of QCD using Monte Carlo methods with space-time lattices is described. The extraction of excited-state energies necessitates the evaluation of correlation matrices of sets of operators, and the importance of extended three-quark operators to capture both the radial and orbital structures of baryons is emphasized. The use of both quark-field smearing and link-field smearing in the operators is essential for reducing the couplings of the operators to the high-frequency modes and for reducing statistical noise in the correlators. The extraction of nine energy levels in a given symmetry channel is demonstrated, and identifying the continuum spin quantum numbers of the level is discussed.