The reconstruction of supersymmetric theories at high energy scales

Abstract

The reconstruction of fundamental parameters in supersymmetric theories requires the evolution to high scales, where the characteristic regularities in mechanisms of supersymmetry breaking become manifest. We have studied a set of representative examples in this context: minimal supergravity and a left-right symmetric extension; gauge mediated supersymmetry breaking; and superstring effective field theories. Through the evolution of the parameters from the electroweak scale the regularities in different scenarios at the high scales can be unravelled if precision analyses of the supersymmetric particle sector at e + e − linear colliders are combined with analyses at the LHC.

Two-loop matching coefficients for the strong coupling in the minimal supersymmetric standard model

“…In the next step, the (L − 1)-loop expression of ζ C2 g is used to arrive at α (6) s (µ C2 th ). With the help of the L-loop β function (with n f = 6, n s = 0 and ng = 0) we then evaluate α (6) s (µ C1 th ) and perform the matching to α (full)…”

“…In addition, one of its most attractive features is the possibility of unification of the strong, the weak, and the electro-magnetic coupling constants. While having very different numerical values at the electro-weak scale, they may have a common intersection point at a scale µ GUT ∼ 10 16 GeV [1][2][3][4][5][6] which is therefore considered to be the typical scale of a Grand Unified Theory (GUT). In the minimal SM, such an intersection can not be achieved.…”

New allowed mSUGRA parameter space from variations of the trilinear scalar couplingA0

“…As the top quark is much heavier than the bottom quark and the tau lepton, the slope of A t is smaller for small tan β (Fig.2). The coefficients d ′ k depend additionally on the gauge couplings and are of order unity [15]. The RG evolution of A u,d,l from the GUT to the EW scale generates the corresponding terms of the SUSY breaking part of the Lagrangian in the low energy limit:…”

Physics possibilities at a linear collider

“…In [42] the evolution in minimal supergravity (mSUGRA), in left-right supergravity, in gauge mediated SUSY breaking and in superstring induced SUSY breaking models is analysed and the RGE are given. In figure 8 from [43] the evolution of the gaugino mass parameters and of the first generation sfermion mass parameters is shown in the mSUGRA scenario SPS1a [33], where the experimental errors at the electroweak scale .…”