Article

# Yukawa coupling unification in SO(10) with positive \mu\ and a heavier gluino

(Impact Factor: 4.86). 06/2012; 86(3). DOI: 10.1103/PhysRevD.86.035019
Source: arXiv

ABSTRACT The t-b-tau unification with positive Higgs mass parameter \mu\ in the
minimal supersymmetric standard model prefers "just so" Higgs splitting and a
light gluino < 500 GeV which appears to be ruled out by the recent LHC
searches. We reanalyze constraints on soft supersymmetry breaking parameters in
this scenario allowing independent splittings among squarks and Higgs doublets
at the grand unification scale and show that it is possible to obtain t-b-tau
unification and satisfy experimental constraints on gluino mass without raising
supersymmetry breaking scale to very high value ~ 20 TeV. We discuss the origin
of independent squark and Higgs splittings in realistic SO(10) models. Just so
Higgs splitting can be induced without significantly affecting the t-b-tau
unification in SO(10) models containing Higgs fields transforming as
10+\bar{126}+126+210. This splitting arises in the presence of non-universal
boundary conditions from mixing between 10 and other Higgs fields. Similarly,
if additional matter fields are introduced then their mixing with the matter
multiplet 16 is shown to generate the squark splitting required to raise the
gluino mass within the t-b-tau unified models with positive \mu.

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