Yukawa coupling unification in S O ( 10 ) with positive μ and a heavier gluino

Physical review D: Particles and fields (Impact Factor: 4.86). 06/2012; 86(3). DOI: 10.1103/PhysRevD.86.035019
Source: arXiv


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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Available from: Ketan M Patel, Jun 28, 2014
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    • "The effects of these supersymmetric threshold corrections are important especially in the era of precision Higgs couplings and flavor physics and has been a part of many analysis. For some recent work, see [4] [5] [6] [7] [8] [9] [10] [11]. "
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    ABSTRACT: Threshold corrections to the bottom quark mass are often estimated under the approximation that tan$\beta$ enhanced contributions are the most dominant. In this work we revisit this common approximation made to the estimation of the supersymmetric threshold corrections to the bottom quark mass. We calculate the full one-loop supersymmetric corrections to the bottom quark mass and survey a large part of the phenomenological MSSM parameter space to study the validity of considering only the tan$\beta$ enhanced corrections. Our analysis demonstrates that this approximation severely breaks down in parts of the parameter space. The size of the threshold corrections has significant consequences for the estimation of fits to the bottom quark mass, couplings to Higgses, and flavor observables, and therefore the approximate expressions must be replaced with the full contributions for accurate estimations.
    Journal of High Energy Physics 11/2014; 2015(5). DOI:10.1007/JHEP05(2015)088 · 6.11 Impact Factor
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    • "Although tbτ YU may be spoiled by the addition of extra fields, realistic charged fermions and neutrino masses can be obtained if we assume that the MSSM Higgs doublets H u,d are a superposition of the components that reside in distinct SO(10) representations [25] [26] [27] [28]. To preserve tbτ YU alongside with correct fermion masses, the contributions to H u,d from the extra Higgs fields must be small (see [29] and references therein). However, if those contributions are sizable we can still have tbτ Quasi-Yukawa unification (QYU) [30]. "
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    ABSTRACT: We study models of supersymmetric grand unification based on the SO(10) gauge group. We investigate scenarios of non-universal gaugino masses including models containing a mixture of two representations of hidden sector chiral superfields. We analyse the effect of excluding mu from the fine-tuning measure, and confront the results with low energy constraints, including the Higgs boson mass, dark matter relic density and supersymmetry bounds. We also determine high scale Yukawa coupling ratios and confront the results with theoretical predictions. Finally, we present two additional benchmarks that should be explored at the LHC and future colliders.
    Journal of High Energy Physics 08/2014; 2014(12). DOI:10.1007/JHEP12(2014)132 · 6.11 Impact Factor
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    • "Large values of tan β can explain the observed hierarchy between the top and bottom masses [30] and are predicted in minimal SO(10) models since they impose unification of top, bottom and tau Yukawa couplings at the GUT scale ([31] [32]; for some more recent works see e.g. [33] [34] [35] [36] [37] [38] [39]). Therefore, these models are perfect candidates to accommodate enhanced h → γγ rate. "
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