Nonperturbative Comparison Of Clover And Highly Improved Staggered Quarks In Lattice Qcd And The Properties Of The Phi Meson

We compare correlators for pseudoscalar and vector mesons made from valence strange quarks using the clover quark and highly improved staggered quark (HISQ) formalisms in full lattice QCD. We use fully nonperturbative methods to normalize vector and axial vector current operators made from HISQ quarks, clover quarks and from combining HISQ and clover fields. This allows us to test expectations for the renormalization factors based on perturbative QCD, with implications for the error budget of lattice QCD calculations of the matrix elements of clover-staggered b-light weak currents, as well as further HISQ calculations of the hadronic vacuum polarization. We also compare the approach to the (same) continuum limit in clover and HISQ formalisms for the mass and decay constant of the phi meson. Our final results for these parameters, using single-meson correlators and allowing an uncertainty for the neglect of quark-line disconnected diagrams are: M-phi = 1.023(6) GeV and f(phi) = 0.238(3) GeV in good agreement with experiment. The results come fromcalculations in the HISQformalism using gluon fields that include the effect of u, d, s and c quarks in the sea with three lattice spacing values and mu/d values going down to the physical point.