Related papers: Threshold corrections to hard supersymmetric relat…
We compute one-loop threshold corrections to non-abelian gauge couplings in four-dimensional heterotic vacua with spontaneously broken $\cal N = 2 \to \cal N = 0$ supersymmetry, obtained as Scherk-Schwarz reductions of six-dimensional K3…
We present the decay widths of the heavier Higgs bosons $H^0$ and $A^0$ into chargino pairs in the minimal supersymmetric standard model, including full one-loop corrections. All parameters for charginos are renormalized in the on-shell…
We analyze the supersymmetric (SUSY) QCD contribution to the $h^0 b \bar{b}$ coupling at one loop in the Minimal Supersymmetric Model (MSSM) in the decoupling limit. Analytic expressions in the large SUSY mass region are derived and the…
We present a one-loop calculation of the oblique S and T parameters within strongly-coupled models of electroweak symmetry breaking with a light Higgs-like boson. We use a general effective Lagrangian, implementing the chiral symmetry…
We compute the one-loop gauge couplings in six-dimensional non-Abelian gauge theories on the T^2/Z_2 orbifold with general GUT breaking boundary conditions. For concreteness, we apply the obtained general formulae to the gauge coupling…
The prediction of the strong coupling constant in grand unified theories is reviewed, first in the standard model, then in the supersymmetric version. Various corrections are considered. The predictions in both supergravity-induced and…
The mass spectrum of the chargino--neutralino sector in the minimal supersymmetric standard model (MSSM) is calculated at the one-loop level, based on the complete set of one-loop diagrams. On-shell renormalization conditions are applied to…
We compute one-loop quantum corrections to gravitational couplings in the effective action of four-dimensional heterotic strings where supersymmetry is spontaneously broken by Scherk-Schwarz fluxes. We show that in both heterotic and type…
The physics potential of the Large Hadron Collider in combination with the planned International Linear Collider is discussed for a difficult region of supersymmetry that is characterized by scalar SUSY particles with masses around 2 TeV.…
This paper is devoted to reconsider the one-loop oblique corrections arising from the scalar superpartners in the MSSM, i.e, the squarks, the sleptons and the scalars in Higgs sector. We explicitly present the complete one-loop forms of…
We deal with extensions of the Standard Model by adding horizontal interactions between particle generations. We calculate two loop corrections caused by the presence of coupling between hypothetical horizontal gauge bosons and matter…
Electroweak radiative corrections can be evaluated in the Sudakov approximation, a systematic high energy expansion known to be relevant for the analysis of future collider experiments in the TeV energy range. In the Minimal Supersymmetric…
We show that large string threshold corrections can reconcile the string and MSSM unification scales in fermionic strings. This requires at least three moduli with large VEVs which are different from each other and MSSM states arising in an…
We calculate the two-loop matching corrections for the gauge couplings at the Grand Unification scale in a general framework that aims at making as few assumptions on the underlying Grand Unified Theory (GUT) as possible. In this paper we…
In supersymmetry, the Higgs quartic couplings is given by the sum in quadrature of the weak gauge couplings. This leads to the prediction of a light Higgs boson, which still holds when considering loop corrections from soft supersymmetry…
Precision gauge coupling unification is one of the primary quantitative successes of low energy or split supersymmetry. Preserving this success puts severe restrictions on possible matter and gauge sectors that might appear at…
We compute threshold effects to gauge couplings in four-dimensional $Z_N$ orientifold models of type I strings with ${\cal N}=2$ and ${\cal N}=1$ supersymmetry, and study their dependence on the geometric moduli. We also compute the…
We show that one loop GUT scale threshold corrections to gauge couplings are a significant constraint on the GUT symmetry breaking sector of the theory. The one loop threshold corrections relate the prediction for $\alpha_s(M_Z)$ to the…
The precise determination of the Higgs self-couplings is an essential task for understanding electroweak symmetry breaking and probing physics beyond the Standard Model (SM). The calculation of two-loop corrections to scalar couplings is…
We calculate the tree-level expressions for the electroweak precision observables in the SU(5)/SO(5) littlest Higgs model. The source for these corrections are the exchange of heavy gauge bosons, explicit corrections due to non-linear…