Teppei Kitahara

Probing Bino contribution to muon g − 2

A bstractWe study SUSY models in which Bino contributions solve the muon g − 2 anomaly. The contributions are enhanced by large left-right mixing of the smuons. However, it is constrained by the vacuum stability condition of the slepton-Higgs potential. Therefore, there are upper bounds on masses of sleptons and Bino. When the slepton soft masses are universal, the upper bound on the smuon mass becomes 330 (460) GeV in order to solve the g − 2 anomaly at the 1σ (2σ) level. It is within the reach of LHC and ILC. If the stau is heavier than the smuon, the bound can be as large as 1.4 (1.9) TeV. Such non-universal slepton mass spectrum generically predicts too large LFV/CPV. We show that the models are expected to be probed by LHC/ILC and LFV/CPV complementarily in future.

Gauge invariant Barr-Zee type contributions to fermionic EDMs in the two-Higgs doublet models

A bstractWe calculate all gauge invariant Barr-Zee type contributions to fermionic electric dipole moments (EDMs) in the two-Higgs doublet models (2HDM) with softly broken Z2 symmetry. We start by studying the tensor structure of h → VV′ part in the Barr-Zee diagrams, and we calculate the effective couplings in a gauge invariant way by using the pinch technique. Then we calculate all Barr-Zee diagrams relevant for electron and neutron EDMs. We make bounds on the parameter space in type-I, type-II, type-X, and type-Y 2HDMs. The electron and neutron EDMs are complementary to each other in discrimination of the 2HDMs. Type-II and type-X 2HDMs are strongly constrained by recent ACME experiment’s result, and future experiments of electron and neutron EDMs may search

Stau with large mass difference and enhancement of h → γγ decay rate in the MSSM

\mathcal{O}

Vacuum Stability Constraints on the Enhancement of the Higgs to Diphoton Rate in the MSSM

(10) TeV physics.

Vacuum stability constraints on the enhancement of the h → γγ rate in the MSSM

A bstractThe ATLAS and the CMS collaborations have presented results which show an excess of the h → γγ decay channel. In the Minimal Supersymmetric Standard Model (MSSM), this situation can be achieved by a light stau and a large left-right mixing of the staus. However, this parameter region is severely constrained by vacuum stability. In order to relax the vacuum meta-stability condition, we focus on the parameter region where the mass difference between the two staus is large. This region has not been considered yet. In this paper, we show that staus with a large mass difference can relax the vacuum meta-stability condition sufficiently even if the lighter stau mass

Prospects for Spin-1 Resonance Search at 13 TeV LHC and the ATLAS Diboson Excess

{m_{{{{{\widetilde{\tau}}}_1}}}}

Singularity-free next-to-leading order ΔS = 1 renormalization group evolution and ϵK′/ϵK in the Standard Model and beyond

is kept light. We find that when the mass difference of two staus is large, the enhancement of the h → γγ decay rate becomes small in spite of a relaxation of the vacuum meta-stability condition. Because of this feature, an

Protophobic light vector boson as a mediator to the dark sector

\mathcal{O}

Reconstructing supersymmetric contribution to muon anomalous magnetic dipole moment at ILC

(70)% enhancement of Γ(h → γγ)/Γ(h → γγ)SM is difficult to achieve in the light stau scenario in the MSSM.

Revisiting kaon physics in general Z scenario

A bstractThe ATLAS and CMS collaborations discovered a new boson particle. If the new boson is the Higgs boson, the diphoton signal strength is 1.5 - 1.8 times larger than the Standard Model (SM) prediction, while the W W and ZZ signal strengths are in agreement with the SM one. In the Minimal Supersymmetric Standard Model (MSSM), overall consistency can be achieved by a light stau and the large left-right mixing of staus. However, a light stau and large left-right mixing of staus may suffer from vacuum instability. We first apply the vacuum meta-stability condition to the Higgs to diphoton decay rate in the MSSM. We show that the vacuum meta-stablity severely constrains the enhancement to the Higgs to diphoton rate. For example, when the lighter stau mass is 100 GeV, the upper bound on the enhancement to the Higgs to diphoton rate becomes 25%.