THE ρ MESON SPECTRUM AND K π SCATTERING WITH PARTIAL WAVE MIXING IN LATTICE QCD
The finite-volume QCD spectrum in the I = 1, S = 0, parity-odd, G-parity-even channels for zero total momentum is studied using lattice QCD, and the K-matrix for K π scattering is investigated to determine the mass and decay width of the K* (892) from first principles. The recently developed stochastic LapH method has proven to be a valuable tool in lattice QCD calculations when all-to-all quark propagators are needed, as is the case for isoscalar mesons and two-hadron operators. This method is especially important for large volumes where other methods do not scale well. These calculations were done with 412 gauge configurations using clover-improved Wilson fermions on a large anisotropic 323 ⨯ 256 lattice with a pion mass near 240 MeV. The stationary states determined to be single-particle dominated are compared with the experimental resonances and are found to be in reasonable agreement. Additionally, the initial development of tetraquark operators is described.
Co-advisor: Dr. Colin Morningstar, CMU