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arXiv · 1602.00796

S-parameter and vector decay constant in QCD with eight fundamental fermions

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

SU(3) gauge theory with eight massless fundamental fermions seems to be near the conformal boundary, and is a candidate theory of walking technicolor. Along the series of study by LatKMI collaboration using HISQ fermions, S-parameter and vector decay constant, which provide important constraints in the model of electroweak symmetry breaking, are calculated for this theory. Use of various volumes allows a systematic investigation of finite volume effects. A strong sensitivity of the S-parameter to the volume is found.

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LatKMI collaboration, Yasumichi Aoki, Tatsumi Aoyama, Ed Bennett, Masafumi Kurachi, Toshihide Maskawa, Kohtaroh Miura, Kei-ichi Nagai, Hiroshi Ohki, Enrico Rinaldi, Akihiro Shibata, Koichi Yamawaki, Takeshi Yamazaki. 2016-02-02. S-parameter and vector decay constant in QCD with eight fundamental fermions. https://arxiv.org/abs/1602.00796

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