Limit on mass differences in the Weinberg model

Abstract

Within the Weinberg model mass differences between members of a multiplet generate further mass differences between the neutral and charged vector bosons. The experimental situation on the Weinberg model leads to an upper limit of about 800 GeV on mass differences within a multiplet. No limit on the average mass can be deduced.

Precise prediction forMWin the MSSM

“…The former receives large fermionic contributions from the shift in the fine structure constant due to light fermions, ∆α ∝ log(m f /M Z ), a pure SM contribution. The latter involves the leading universal corrections induced by the mass splitting between fields in an isospin doublet [43],…”

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