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Non-Universal Gaugino Masses and Natural Supersymmetry

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 نشر من قبل Ilia Gogoladze
 تاريخ النشر 2012
  مجال البحث
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We demonstrate that natural supersymmetry is readily realized in the framework of SU(4)_c times SU(2)_L times SU(2)_R with non-universal gaugino masses. Focusing on ameliorating the little hierarchy problem, we explore the parameter space of this model which yields small fine-tuning measuring parameters (natural supersymmetry) at the electroweak scale (Delta_{EW}) as well as at high scale (Delta_{HS}). It is possible to have both Delta_{EW} and Delta_{HS} less than 100 in these models, (2 % or better fine-tuning), while keeping the light CP-even (Standard Model-like) Higgs mass in the 123 GeV-127 GeV range. The light stop quark mass lies in the range 700 GeV <m_{tilde{t}_{1}}< 1500 GeV, and the range for the light stau lepton mass is 900 GeV <m_{tilde{tau}_{1}}< 1300 GeV. The first two family squarks are in the mass range 3000 GeV <m_{tilde{t}_{1}}< 4500 GeV, and for the gluino we find 2500 GeV <m_{tilde{g}_{1}}< 3500 GeV. We do not find any solution with natural supersymmetry which yields significant enhancement for Higgs production and decay in the diphoton channel.



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