Related papers: Natural Effective Supersymmetry
We extend the Standard Model (SM) by adding a pair of fermionic SU(2)-doublets with opposite hypercharge and a fermionic SU(2)-triplet with zero hypercharge. We impose a discrete Z_2-symmetry that distinguishes the SM fermions from the new…
We show that matter yukawa couplings of the New Minimal Supersymmetric (SO(10)) GUT(NMSGUT) are subject to very significant GUT scale threshold corrections. Including these threshold effects relaxes the constraint $ y_b-y_\tau\simeq…
We propose the minimal (Least) version of the Supersymmetric Standard Model which can solve the hierarchy problem in the same way as the so-called Minimal Supersymmetric Standard Model (MSSM) and presents solutions to some of its problems.…
We compute the leading QCD corrections to K-Kbar mixing in the supersymmetric standard model with general soft supersymmetry-breaking parameters. We construct the \Delta S=2 effective Lagrangian for three hierarchies of supersymmetric…
We point out that a class of non-supersymmetric models based on the gauge group $SU(3)_C \times SU(2)_L\times SU(2)_R\times U(1)_{Y_L}\times U(1)_{Y_R}$ possesses an automatic, exact $Z_{2 }$ symmetry under which the fermions in the…
The first 1/fb of LHC searches have set impressive limits on new colored particles decaying to missing energy. We address the implication of these searches for naturalness in supersymmetry (SUSY). General bottom-up considerations of natural…
Requiring that the contributions of supersymmetric particles to the Higgs mass are not highly tuned places upper limits on the masses of superpartners -- in particular the higgsino, stop, and gluino. We revisit the details of the tuning…
The various experimental bounds on flavor-changing interactions severely restrict the low-energy flavor structures of soft supersymmetry breaking parameters. In this work, we show that with a particular assumption of Yukawa couplings, the…
In a model with a gauge group $G_{SM}\otimes U(1)_X$, where $G_{SM} \equiv SU(3)_C \otimes SU(2)_L \otimes U(1)_Y$ is the standard model gauge group and $U(1)_X$ is a horizontal local gauge symmetry, the spectrum of charged fermion masses…
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…
We construct a model of spontaneous CP violation in E6 supersymmetric grand unified theory. In the model, we employ an SU(2)F flavor symmetry and an anomalous U(1)A symmetry. The SU(2)F flavor symmetry is introduced to provide the origin of…
It has been shown that, in the context of the MSSM, the Supersymmetric Flavour Problem cannot be solved by just letting the sfermions of the first two generations be relatively heavy. The reason is twofold: naturalness of the Fermi scale on…
The existence of extra chiral generations is strongly disfavored by the precision electroweak data if all the extra fermions are heavier than m_Z. However fits as good as the SM can be obtained if one allows the new neutral leptons to have…
Two-loop threshold corrections for both the strong coupling constant and Yukawa couplings of heavy SM fermions are considered in the context of Minimal Supersymmetric Standard Model (MSSM). With the help of the well-known SOFTSUSY code the…
First we give a review of the spurion formalism and the exact renormalization group equations for soft supersymmetry breaking parameters in general gauge theories. Next we discuss the minimal supersymmetric standard model coupled to…
Supersymmetry broken by anomaly mediation suffers from tachyonic slepton masses. A possible solution to this problem results in "decoupling", i.e., the first two generations of sfermions are much heavier than the third one. We note that in…
We propose a top hypercharge model with gauge symmetry SU(3)_C x SU(2)_L x U(1)_1 x U(1)_2 where the first two families of the Standard Model (SM) fermions are charged under U(1)_1 while the third family is charged under U(1)_2. The U(1)_1…
Semi-inclusive decays, $\hlx$, are studied in the framework of the minimal supersymmetric standard model without $R-$parity, where $\qh$ ($\ql$) are the second or third (first or second) generation quarks with the same charge and $\xi$ is a…
We study soft SUSY breaking parameters in the Nelson-Strassler type of models: SUSY standard models coupled with SCFTs. In this type of models, soft SUSY breaking parameters including sfermion masses can be suppressed around the decoupling…
We discuss issues in a scenario that hierarchical Yukawa couplings are generated through strong dynamics of superconformal field theories (SCFTs). Independently of mediation mechanism of supersymmetry breaking, infrared convergence property…