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arXiv · 1608.07478

Studying the $ρ$ resonance parameters with staggered fermions

Ziwen Fu·Lingyun Wang
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Abstract

We deliver a lattice study of $ρ$ resonance parameters with p-wave $ππ$ scattering phases, which are extracted by finite-size methods at one center-of-mass frame and four moving frames for six MILC lattice ensembles with pion masses ranging from $346$ to $ 176$ MeV. The effective range formula is applied to describe the scattering phases as a function of the energy covering the resonance region, this allows us to extract $ρ$ resonance parameters and to investigate the quark-mass dependence. Lattice studies with three flavors of the Asqtad-improved staggered fermions enable us to use the moving-wall source technique on large lattice spatial dimensions ($L=64$) and small light $u/d$ quarks. Numerical computations are carried out at two lattice spacings, $a \approx 0.12$ and $0.09$ fm.

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Ziwen Fu, Lingyun Wang. 2016-08-26. Studying the $ρ$ resonance parameters with staggered fermions. https://doi.org/10.1103/physrevd.94.034505

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