A precision constraint on multi-Higgs-doublet models

Journal of Physics G Nuclear and Particle Physics (Impact Factor: 5.33). 12/2007; DOI: 10.1088/0954-3899/35/7/075001
Source: arXiv

ABSTRACT We derive a general expression for Delta rho (or, equivalently, for the oblique parameter T) in the SU(2) x U(1) electroweak model with an arbitrary number of scalar SU(2) doublets, with hypercharge +-1/2, and an arbitrary number of scalar SU(2) singlets. The experimental bound on Delta rho constitutes a strong constraint on the masses and mixings of the scalar particles in that model.

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