Technicolor Theories with Negative S
نویسندگان
چکیده
We show that the pseudo Nambu–Goldstone boson contribution to the Peskin–Takeuchi electroweak parameter S can be negative in a class of technicolor theories. This negative contribution can be large enough to cancel the positive techni-hadron contribution, showing that electroweak precision tests alone cannot be used to rule out technicolor as the mechanism of electroweak symmetry breaking. PACS numbers 12.15.Cc, 14.80.Gt This work was supported in part by the Director, Office of Energy Research, Office of High Energy and Nuclear Physics, Division of High Energy Physics of the U.S. Department of Energy under contract DE-AC03-76SF00098 and in part by the National Science Foundation under grant PHY90-21139.
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تاریخ انتشار 1992