1998/01/31 by K. Agashe, Kaustubh Agashe, Michael L. Graesser +1 · 39 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Minimal Supersymmetric Standard Model #Particle physics #Particle physics theoretical and experimental studies #Physics #Scalar (mathematics) #Supersymmetry #Supersymmetry breaking #Yukawa potential #hep-ph
paper · pdf · doi:10.1103/physrevd.59.015007
published in Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields 59(1) (American Physical Society) · Latex, 40 pages, 14 figures. Replacing an earlier version of the manuscript. Extra section added discussing limits on $δ$ from finetuning, positivity and $Δm_K$. Earlier version did not include the one-loop hypercharge $D-$term; this has been corrected, and our conclusions remain unchanged
arxiv created 1998/07/01 · openalex publication_date 1998/11/30 · arxiv updated 2014/11/17 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The supersymmetric contributions to the flavor changing neutral current processes may be suppressed by decoupling the scalars of the first and second generations. It is known, however, that the heavy scalars drive the top squark mass squareds negative through the two-loop renormalization group evolution. This tension is studied in detail. Two new items are included in this analysis: the effect of the top quark Yukawa coupling and the QCD corrections to the supersymmetric contributions to \ensuremathΔmK. Even with Cabibbo-like degeneracy between the squarks of the first two generations, these squarks must be heavier than \ensuremath∼40 TeV to suppress \ensuremathΔmK. This implies, in the case of a high scale of supersymmetry breaking, that the boundary value of the top squark mass has to be greater than \ensuremath∼7 TeV to keep the top squark mass squared positive at the weak scale. Low-energy supersymmetry breaking at a scale that is of the same order as the mass of the heavy scalars is also considered. In this case the finite parts of the two-loop diagrams are computed to estimate the contribution of the heavy scalar masses to the top squark mass squared. It is found that for Cabibbo-like mixing between the squarks, the top squark mass at the boundary needs to be larger than \ensuremath∼2 TeV. Thus, for both cases, the large boundary value of the top squark masses leads to an unnatural amount of fine tuning to obtain the correct Z mass.