Isospin breaking and fine-tuning in top-color assisted technicolor

  title={Isospin breaking and fine-tuning in top-color assisted technicolor},
  author={R. Sekhar Chivukula and Bogdan A. Dobrescu and John Terning},
  journal={Physics Letters B},
Recently, Hill has proposed a model in which new, potentially low-energy, top-color interactions produce a top-condensate (a la Nambu-Jona-Lasinio) and accommodate a heavy top quark, while technicolor is responsible for producing the W and Z masses. Here we argue that isospin breaking gauge interactions, which are necessary in order to split the top and bottom quark masses, are likely to couple to technifermions. In this case they produce a significant shift in the W and Z masses (i.e… Expand
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