Related papers: Two-loop mass splittings in electroweak multiplets…
We reexamine the simplified dark matter (DM) models with fermionic DM particle and spin-0 mediator. The DM-nucleon scattering cross sections of these models are low-momentum suppressed at tree-level, but receive sizable loop-induced…
The spectrum of Weakly-Interacting-Massive-Particle (WIMP) dark matter generically possesses bound states when the WIMP mass becomes sufficiently large relative to the mass of the electroweak gauge bosons. The presence of these bound states…
Electroweak second order shifts of muonium ($\mu^+e^-$ bound state) energy levels are calculated for the first time. Calculation starts from on-shell one-loop elastic $\mu^+ e^-$ scattering amplitudes in the center of mass frame, proceed to…
Two-loop contributions to the muon (g-2) from fermion/sfermion loops in the MSSM are presented, and an overview of the full MSSM prediction for (g-2) is given with emphasis on the behaviour in scenarios which are compatible with LHC data,…
Masses of heavy Standard Model fermions (top-quark, bottom-quark, and tau-lepton) play an important role in the analysis of theories beyond the SM. They serve as low-energy input and reduce the parameter space of such theories. In this…
High-precision electroweak experiments such as parity-violating Moller scattering can provide indirect access to physics at multi-TeV scales and play an important complementary role to the LHC research program. However, before physics of…
We provide a unified presentation of extensions of the Minimal Dark Matter framework in which new fermionic electroweak multiplets are coupled to each other via the Standard Model Higgs doublet. We study systematically the generic features…
In this proceeding, we highlight the computation of leading fermionic three-loop corrections to electroweak precision observables (EWPOs) accomplished recently. We summarize the numerical analysis and provide an outlook.
The one-loop corrections to the weak mixing angle $\sin^2\theta_{eff}^b$ derived from the $Z{\bar b}b$ vertex, are known since 1985. It took another 30 years to calculate the complete electroweak two-loop corrections to…
We calculate the SU(2)$\times$U(1) electroweak static potential between a fermionic triplet in the broken phase of the Standard Model in the one-loop order (NLO). The one-loop correction provides the leading non-relativistic correction to…
Leptophilic sub-MeV spin-zero dark matter (DM) decays into photons via one-loop processes, a scenario that has been in part overlooked in current literature. In this work, we provide updated and comprehensive upper limits on scalar,…
We propose a "scotogenic" mechanism relating small neutrino mass and cosmological dark matter. Neutrinos are Dirac fermions with masses arising only in two--loop order through the sector responsible for dark matter. Two triality symmetries…
Massive vector-like electroweak doublets are generic in many extensions of the standard model. Even though one member of the doublet is necessarily electrically charged these particles are not easily detected in collider experiments. The…
We examine the relic density of the light mass dark matter region in the inert doublet model (IDM) when the dominant process is due to co-annihilation between the lightest neutral scalars of the model. The full one-loop electroweak…
We calculate the full one-loop electroweak (FEW) corrections to $H^-\to\widetilde{\chi}^-_1\widetilde{\chi}^0_i$ in the minimal supersymmetric standard model (MSSM), and compare with the leading order (LO) corrections including the loops of…
We have redone a recent two-loop computation of the critical mass for Wilson fermions in lattice QCD by evaluating Feynman integrals with the coordinate-space method. We present the results for different types of infrared regularization. We…
We perform a detailed study of an effective field theory which includes the Standard Model particle content extended by a pair of Weyl fermionic SU(2)-doublets with opposite hypercharges. A discrete symmetry guarantees that a linear…
If the Dark Matter is the neutral Majorana component of a multiplet which is charged under the electroweak interactions of the Standard Model, its main annihilation channel is into W+W-, while the annihilation into light fermions is…
A minimal supersymmetric version of the Standard Model with complex parameters allows contributions to the weak-electric dipole moments of fermions at the one-loop level. Assuming generation-diagonal trilinear soft-susy-breaking terms and…
The running of the effective electromagnetic coupling is for many electroweak observables the dominant correction. It plays an important role for deriving constraints on the Standard Model in the context of electroweak precision…