Pseudoscalar flavor-singlets and staggered fermions
نویسندگان
چکیده
The Asqtad improved staggered fermion formalism has been a valuable tool in successfully calculating the non-singlet parts of the hadronic spectrum. We are engaged in a project to calculate the spectrum of the pseudoscalar singlet mesons with 2 + 1-flavor Asqtad staggered gauge configurations. Propagators of flavor-singlet states incorporate contributions from both disconnected and connected diagrams, and hence are sensitive to any differences in the actions governing the sea and valence fermions on the lattice. As such, they also present the possibility of a probe of the validity of the “fourth-root trick” in the staggered fermion formulation. We present an update on our progress toward measuring the η ′ mass on 2+1-flavor Asqtad staggered gauge configurations, including a review of methods and preliminary results. We also show a strong correlation between Tr(γ5 ⊗ 1) and the topological charge in these configurations, as predicted by the index theorem.
منابع مشابه
ar X iv : 0 71 0 . 17 25 v 1 [ he p - la t ] 9 O ct 2 00 7 Pseudoscalar Flavor - Singlet Physics with Staggered
Accurately calculating the mass of flavor-singlet meson states from numerical lattice simulations is an important milestone for lattice QCD. Careful measurement of the full pseudoscalar flavorsinglet propagator is also a crucial step in understanding the dynamics of the fermion sea on the lattice, in particular for potentially non-trivial formulations such as with 2+1-flavor staggered fermions....
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