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arXiv · hep-ph/9403343

Effective Lagrangian for a Technicolor Model without Exact Custodial Symmetry

T. Yoshikawa·H. Takata·T. Morozumi
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Abstract

Effective Lagrangian including technimesons is constructed for a realistic one-family Technicolor model without exact custodial symmetry. Tree level contribution to oblique correction parameters $S$ and $U$ due to spin 1 technimesons are computed with the effective Lagrangian. An isospin breaking term which is associated with technilepton vector mesons gives a negative contribution to the electroweak radiative correction parameter $S$ due to mixing between $I=0$ and $I=1$ vector mesons. $U$ receives non-zero contribution due to exotic left-handed charged vector mesons and its sign can be both negative and positive.

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T. Yoshikawa, H. Takata, T. Morozumi. 1994-05-06. Effective Lagrangian for a Technicolor Model without Exact Custodial Symmetry. https://doi.org/10.1143/ptp%2F92.2.353

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