Friday, February 22, 2013

1302.5262 (D. M. Ghilencea)

Fixing the EW scale in supersymmetric models after the Higgs discovery    [PDF]

D. M. Ghilencea
TeV-scale supersymmetry was originally introduced to solve the hierarchy problem and therefore fix the electroweak (EW) scale in the presence of quantum corrections. Surprisingly, the numerical methods that evaluate the likelihood (or chi^2=-2*ln L) to fit the experimental data and test the SUSY models do not account for fixing the EW scale. When this constraint is implemented, the likelihood (or chi^2) receives a significant correction (delta_chi^2) that worsens the data fits of the models. We estimate this correction for the models: constrained MSSM (CMSSM), models with non-universal gaugino masses (NUGM) or higgs soft masses (NUHM1, NUHM2), the NMSSM and the general NMSSM (GNMSSM). Except the GNMSSM model and for a higgs mass m_h=126 GeV, one finds that in these models (delta_chi^2)/ndf >1.5, which violates the usual condition of a good fit already before fitting the observables, other than the EW scale itself (ndf=number of degrees of freedom). Given its significant (negative) implications for SUSY models, it is suggested that future data fits properly account for this effect, if one remains true to the original goal of SUSY.
View original: http://arxiv.org/abs/1302.5262

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