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We utilize a previously constructed thermodynamic T-matrix approach to the quark-gluon plasma (QGP) to derive constaints on its input by using results on Wilson line correlators (WLCs) of a static quark-antiquark pair from 2 + 1-flavor lattice-QCD (lQCD) computations with realistic pion mass. The self-consistent T-matrix results, which include previous constraints from the lQCD equation of state in the light-parton sector, can describe the lQCD data for WLCs fairly well once refinements of its driving kernel are applied. In particular, the input potential requires less screening than what has been inferred from previous T-matrix analyses. Pertinent predictions for the spectral and transport properties of the QGP are discussed, including the spatial diffusion coefficient for heavy quarks; the latter turns out to have a rather weak temperature dependence, in approximate agreement with recent unquenched lQCD results. [ABSTRACT FROM AUTHOR]

Amplitudes of the form γ ∗ (q 2) → γ P 1 P 2 appear as sub-processes in the computation of the muon g - 2 . We test a proposed theoretical modelling against very precise experimental measurements by the KLOE collaboration at q 2 = m ϕ 2 . Starting from an exact, parameter-free dispersive representation for the S-wave satisfying QCD asymptotic constraints and Low's soft photon theorem we derive, in an effective theory spirit, a two-channel Omnès integral representation which involves two subtraction parameters. The discontinuities along the left-hand cuts which, for timelike virtualities, extend both on the real axis and into the complex plane are saturated by the contributions from the light vector mesons. In the case of P 1 P 2 = π η , we show that a very good fit of the KLOE data can be achieved with two real parameters, using a T-matrix previously determined from γ γ scattering data. This indicates a good compatibility between the two data sets and confirms the validity of the T-matrix. The resulting amplitude is also found to be compatible with the chiral soft pion theorem. Applications to the I = 1 scalar form factors and to the a 0 (980) resonance complex pole are presented. [ABSTRACT FROM AUTHOR]