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Charmonium current-current correlators with Mobius domain-wall fermion

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 Added by Katsumasa Nakayama
 Publication date 2015
  fields
and research's language is English




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We calculate the charmonium correlators on the lattice with $n_f = 2+ 1$ Moebius domain wall fermion, and extract the charm quark mass and the strong coupling constant. Time moments are defined by current-current correlators, which have been calculated in the continuum theory by perturbation theory. We extract the charm quark mass by matching the lattice results with the corresponding perturbative QCD calculations, using the recently generated ensembles by the JLQCD collaboration at lattice spacings $a = 0.083, 0.055$, and $0.044$ fm.



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We extract the charm quark mass and the strong coupling constant from the charmonium current correlators calculated with $n_f = 2 + 1$ Mobius domain wall fermions. We match our lattice calculation for the temporal moments of the correlator with perturbative result known up to four-loop order, and extract the charm quark mass with uncertainty less than 1%. Using the temporal moments, we also confirm the correlators in the vector channel to be consistent with the experimental data for the R-ratio. We used the ensembles generated by the JLQCD collaboration at lattice spacings $a$ = 0.080 fm, 0.055 fm and 0.044 fm.
We calculate the spectral function of the QCD Dirac operator using the four-dimensional effective operator constructed from the Mobius domain-wall implementation. We utilize the eigenvalue filtering technique combined with the stochastic estimate of the mode number. The spectrum in the entire eigenvalue range is obtained with a single set of measurements. Results on 2+1-flavor ensembles with Mobius domain-wall sea quarks at lattice spacing ~ 0.08 fm are shown.
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