2002/04/10 by T. T. Takahashi, H. Suganuma, Y. Nemoto +1 · 1 citation
Physics and Astronomy · #hep-lat
paper · pdf · doi:10.1103/physrevd.65.114509
published as Phys.Rev. D65 (2002) 114509 · 30 pages, 14 figures and 13 tables submitted to Phys.Rev.D
arxiv created 2002/04/10 · arxiv updated 2009/11/30
The static three-quark (3Q) potential is studied in detail using SU(3) lattice QCD with 123 × 24 at β=5.7 and 163 × 32 at β=5.8, 6.0 at the quenched level. For more than 300 different patterns of the 3Q systems, we perform the accurate measurement of the 3Q Wilson loop with the smearing method, which reduces excited-state contaminations, and present the lattice QCD data of the 3Q ground-state potential V\rm 3Q. We perform the detailed fit analysis on V\rm 3Q in terms of the Y-ansatz both with the continuum Coulomb potential and with the lattice Coulomb potential, and find that the lattice QCD data of the 3Q potential V\rm 3Q are well reproduced within a few % deviation by the sum of a constant, the two-body Coulomb term and the three-body linear confinement term σ\rm 3Q L\rm min, with L\rm min the minimal value of the total length of color flux tubes linking the three quarks. From the comparison with the Q- \rm Q potential, we find a universality of the string tension as σ\rm 3Q ≃ σ\rm Q Q and the one-gluon-exchange result for the Coulomb coefficients as A\rm 3Q ≃ \frac12 A\rm Q Q. We investigate also the several fit analyses with the various ansätze: the Y-ansatz with the Yukawa potential, the Δ-ansatz and a more general ansatz including the Y and the Δ ansätze in some limits. All these fit analyses support the Y-ansatz on the confinement part in the 3Q potential V\rm 3Q, although V\rm 3Q seems to be approximated by the Δ-ansatz with σΔ≃ 0.53 σ.