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arXiv · 1403.5000

Light composite scalar in eight-flavor QCD on the lattice

Yasumichi Aoki·Tatsumi Aoyama·Masafumi Kurachi·Toshihide Maskawa·Kohtaroh Miura·Kei-ichi Nagai·Hiroshi Ohki·Enrico Rinaldi·Akihiro Shibata·Koichi Yamawaki·Takeshi Yamazaki
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Abstract

We present the first observation of a flavor-singlet scalar meson as light as the pion in $N_f=8$ QCD on the lattice, using the Highly Improved Staggered Quark action. Such a light scalar meson can be regarded as a composite Higgs with mass 125 GeV. In accord with our previous lattice results showing that the theory exhibits walking behavior, the light scalar may be a technidilaton, a pseudo Nambu-Goldstone boson of the approximate scale symmetry in walking technicolor.

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Yasumichi Aoki, Tatsumi Aoyama, Masafumi Kurachi, Toshihide Maskawa, Kohtaroh Miura, Kei-ichi Nagai, Hiroshi Ohki, Enrico Rinaldi, Akihiro Shibata, Koichi Yamawaki, Takeshi Yamazaki. 2014-05-14. Light composite scalar in eight-flavor QCD on the lattice. https://doi.org/10.1103/physrevd.89.111502

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