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arXiv · 1211.6651

Low energy spectra in many flavor QCD with Nf=12 and 16

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

We present our result of the many-flavor QCD. Information of the phase structure of many-flavor SU(3) gauge theory is of great interest, since the gauge theories with the walking behavior near the infrared fixed point are candidates of new physics for the origin of the dynamical electroweak symmetry breaking. We study the SU(3) gauge theories with 12 and 16 fundamental fermions. Utilizing the HISQ type action which is useful to study the continuum physics, we analyze the lattice data of the mass and the decay constant of the pseudoscalar meson and the mass of the vector meson as well at several values of lattice spacing and fermion mass. The finite size scaling test in the conformal hypothesis is also performed. Our data is consistent with the conformal scenario for Nf=12. We obtain the mass anomalous dimension $γ_m \sim 0.4-0.5$. An update of $N_f=16$ study is also shown.

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Yasumichi Aoki, Tatsumi Aoyama, Masafumi Kurachi, Toshihide Maskawa, Kei-ichi Nagai, Hiroshi Ohki, Akihiro Shibata, Koichi Yamawaki, Takeshi Yamazaki. 2012-11-28. Low energy spectra in many flavor QCD with Nf=12 and 16. https://arxiv.org/abs/1211.6651

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