In a generic Grand Unified Theory with a relatively small dispersion of the spectrum around the Z-boson and the unification masses, a connection is established, exact at one loop level, between M(Z), G(F), alpha(M(Z)) and the strong coupling constant (alpha(3)(M(Z)). At this level of precision, this avoids the logical and phenomenological inconsistency of predicting alpha(3)(M(Z)) by means of the electroweak couplings as extracted from the data in the Standard Model rather than in the complete theory. Attention is paid to the independence of the physical results from regularization and/or renormalization schemes. As a particularly relevant example, the analysis is specialized to the case of the Minimal Supersymmetric Standard Model, with emphasis on light charginos and neutralinos.
LIGHT THRESHOLDS IN GRAND UNIFIED THEORIES
STRUMIA, ALESSANDRO
1995-01-01
Abstract
In a generic Grand Unified Theory with a relatively small dispersion of the spectrum around the Z-boson and the unification masses, a connection is established, exact at one loop level, between M(Z), G(F), alpha(M(Z)) and the strong coupling constant (alpha(3)(M(Z)). At this level of precision, this avoids the logical and phenomenological inconsistency of predicting alpha(3)(M(Z)) by means of the electroweak couplings as extracted from the data in the Standard Model rather than in the complete theory. Attention is paid to the independence of the physical results from regularization and/or renormalization schemes. As a particularly relevant example, the analysis is specialized to the case of the Minimal Supersymmetric Standard Model, with emphasis on light charginos and neutralinos.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
