Mono Vector-Quark Production at the LHC

Vector-like quark is a common feature in many new physics models. We study the vector-like quark production as an s-channel resonance at the Large Hadron Collider for the vector-like quarks mainly mixing with the top- and bottom-quark in the Standard Model. We emphasize that the leptonic angular distribution can be used to discriminate various vector-like quark models.Comment: 29 pages, 11 figures, with some typos fixe

A composite scalar hint from di-boson resonances?

We study the light scalar resonance sector of a composite Higgs model UV embedding based on the coset $SU(4)/Sp(4)$. Beyond the Higgs multiplet, the pseudo Nambu-Goldstone sector of this model contains Standard Model singlets which couple to the Standard Model gauge bosons through Wess-Zumino-Witten anomaly terms. They can thus be produced in gluon fusion and decay into either gluons or pairs of electroweak gauge bosons $WW$, $ZZ$, $Z\gamma$, or $\gamma\gamma$. In this letter we show that one of the pseudo Nambu-Goldstone boson states has appropriate couplings in order to explain a di-boson excess in the $WW$ channel whilst not being excluded by LHC run I bounds on the di-jet, $Z\gamma$ and $\gamma\gamma$ decay channels. A di-boson resonance production cross section of $\sim$ 10 fb at LHC run I is not a prediction of the model, but can be obtained if the confining gauge group is of high rank.Comment: 5 pages, 3 figures, 2 table

Radion dynamics in multibrane Randall-Sundrum model

The radion in the Randall-Sundrum model is stabilized by the back reaction of a bulk scalar field with its VEV depending on the fifth dimensional coordinate. We studied the radion dynamics in an extended scenario, where intermediate branes exist between the UV and IR branes. Our analysis proves that the formalism of EFT delivers the same equations of motion as the linearized Einstein equation with all junction conditions satisfied. The relic of 5d diffeomorphism is broken after including the Goldberger-Wise stabilization and a unique radion field is conjectured as legitimate in the RS metric perturbation.Comment: 6 pages and 1 figure; The proceeding paper for talk presented at the 41st International Conference on High Energy Physics (ICHEP2022), 6-13 July, 2022, Bologna, Ital

D-term Enhancement in Spin-1 Top Partner Model

Supersymmetric models with extended electroweak gauge groups have the potential to enhance the Higgs quartic interaction through nondecoupling D-terms. We consider the D-term enhancement effect in a vector top partner model, where the quadratic divergence to the Higgs mass from the virtual top quark is canceled by its corresponding spin-1 superpartners. We are going to show that the model can predict a Higgs mass beyond the LEP bound, and is consistent with the precision electroweak constraints.Comment: 11 pages, 4 figures and references added, updated EW bound for the mass of vector top partne

Diffeomorphism breaking from radion stabilization

We present for the first time the nonlinear diffeomorphism in the Randall Sundrum model that can keep the effective Lagrangian invariant up to the cubic order. We show that the diffeomorphism shapes the interaction structure and leads to a new conservation law in an exact AdS$_5$ space. However the stabilization of radius via Goldberger-Wise mechanism will spontaneously break the fifth dimensional diffeomorphism. The nonliear property of diffeomorphism also ensures a unique radion field even in the extension of RS model with intermediate branes.Comment: 14 page