arXiv 0804.38712008-04hep-lat

The eta' meson from lattice QCD

ETM Collaboration, K. Jansen, C. Michael, C. Urbach

备注：: 16 pages: version accepted for publication
DOI：: 10.1140/epjc/s10052-008-0764-6

英文摘要：

We study the flavour singlet pseudoscalar mesons from first principles using lattice QCD. With N_f=2 flavours of light quark, this is the so-called eta_2 meson and we discuss the phenomenological status of this. Using maximally twisted-mass lattice QCD, we extract the mass of the eta_2 meson at two values of the lattice spacing for lighter quarks than previously discussed in the literature. We are able to estimate the mass value in the limit of light quarks with their physical masses.

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