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One-loop Radiative Corrections to the rho Parameter in the Littlest Higgs Model

Mu-Chun Chen·Sally Dawson
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Abstract

We perform a one-loop analysis of the rho parameter in the Littlest Higgs model, including the logarithmically enhanced contributions from both fermion and scalar loops. We find the one-loop contributions are comparable to the tree level corrections in some regions of parameter space. The fermion loop contribution dominates in the low cutoff scale f region. On the other hand, the scalar loop contribution dominates in the high cutoff scale f region and it grows with the cutoff scale f. This in turn implies an upper bound on the cutoff scale. A low cutoff scale is allowed for a non-zero triplet VEV. Constraints on various other parameters in the model are also discussed. The role of triplet scalars in constructing a consistent renormalization scheme is emphasized.

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Mu-Chun Chen, Sally Dawson. 2004-04-28. One-loop Radiative Corrections to the rho Parameter in the Littlest Higgs Model. https://doi.org/10.1103/physrevd.70.015003

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