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arXiv · hep-ph/0109126

Scale-independent mixing angles

J. R. Espinosa·I. Navarro
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Abstract

A radiatively-corrected mixing angle has to be independent of the choice of renormalization scale to be a physical observable. At one-loop in MS-bar, this only occurs for a particular value, p*, of the external momentum in the two-point functions used to define the mixing angle: p*^2=(M1^2+M2^2)/2, where M1, M2 are the physical masses of the two mixed particles. We examine two important applications of this to the Minimal Supersymmetric Standard Model: the mixing angle for a) neutral Higgs bosons and b) stops. We find that this choice of external momentum improves the scale independence (and therefore provides a more reliable determination) of these mixing angles.

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J. R. Espinosa, I. Navarro. 2002-05-24. Scale-independent mixing angles. https://doi.org/10.1103/physrevd.66.016004

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