S-parameter and vector decay constant in QCD with eight fundamental   fermions
  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. 
LatKMI collaboration: Yasumichi Aoki (1), Tatsumi Aoyama (1), Ed   Bennett (2,1), Masafumi Kurachi (3), Toshihide Maskawa (1...
hep-lat