Radion-higgs mixing state at the LHC with the KK contributions to the production and decay

In this paper we study the higgs-radion system of the Randall-Sundum model where matter and gauge fields live in the bulk. We take into account the Kalza-Klein(KK) loop correction for the higgs and the raidion coupling to the gauge bosons. Inspired by the LHC data in 2011 where a sign of the higgs boson has been seen at 125 GeV, we fix the one of the mass eigenstate of the higgs-radion mixed state at 125 GeV, and scan over all the other parameters which have not been excluded by the 2011's data. We find the region of parameters where the scalar particle at 125 GeV have branching ratio larger or smaller than that of the Standard Model(SM) higgs significantly. The predicted ratio Br(ZZ)/Br(gamma gamma) also may be different from that of the SM higgs boson.Comment: 13 pages 6 figure

Implications of Muon anomalous magnetic moment for Direct detection of Neutralino Dark Matter

We investigate the implications of the recent measurement of muon anomalous magnetic moment for the direct detection of neutralino dark matter in the three different SUSY models: mSUGRA, a model with non-universal Higgs mass, and an SO(10) GUT model. We consider two extreme scenario for $\Delta a_\mu$ bound, i.e. $27 \times 10^{-10} < \Delta a_\mu < 59 \times 10^{-10}$ (1$\sigma$ bound) and $0 < \Delta a_\mu < 11 \times 10^{-10}$ ($2\sigma$ below). In mSUGRA model, the counting ratio may be above the sensitivity of the future experiments when parameters are within $1\sigma$ bound of $\Delta a_{\mu}$. However, the $\Omega_{\chi}$ tends to be high compared to the currently favored value $\Omega=0.3$. For models with the non-universal scalar masses, the possibility to have the consistent $\Omega_{\chi}$ and the high counting ratio is open up in the region of parameter space where Higgsino mass $\mu$ is smaller than mSUGRA prediction. In particular, in the SO(10) model, the LSP dark matter detection rate may be enhanced by almost one order of magnitude compared to mSUGRA and the model with non-universal Higgs mass, for cosmologically acceptable $\Omega_{\chi} h^2$. The highest detection rate of LSP dark matter occurs in the region where the LSP constitutes a subdominant part of local halo DM. Implication of SUSY mass parameter measurement under the cosmological constraint is also discussed

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

Motivated by ATLAS diboson excess around 2 TeV, we investigate a phenomenology of spin-1 resonances in a model where electroweak sector in the SM is weakly coupled to strong dynamics. The spin-1 resonances, W' and Z', are introduced as effective degrees of freedom of the dynamical sector. We explore several theoretical constraints by investigating the scalar potential of the model as well as the current bounds from the LHC and precision measurements. It is found that the main decay modes are V' -> VV and V' -> Vh, and the V' width is narrow enough so that the ATLAS diboson excess can be explained. In order to investigate future prospects, we also perform collider simulations at the 13 TeV LHC, and obtain a model independent expected exclusion limit for the process pp -> W' -> WZ -> JJ. We find a parameter space where the diboson excess can be explained, and are within a reach of the LHC at the integrated luminosity of 10 fb-1 and 13 TeV.Comment: 38 pages, 19 figures, 1 table; minor changes, references added, version published in JHE

Study of stop and sbottom at LHC

In supersymmetric models a gluino can decay into $tb\tilde{\chi}^{\pm}_1$ through a stop or a sbottom. The decay chain produces an edge structure in the $m_{tb}$ distribution. Monte Carlo simulation studies show that the end point and the edge height would be measured at the CERN LHC by using a sideband subtraction technique. The stop and sbottom masses as well as their decay branching ratios are constrained by the measurement. We study interpretations of the measurement.Comment: 3 pages, 2 eps files, style files are included, talk at PASCOS'03, Mumbai, India, January 3-8, 200

Lepton Energy Asymmetry and Precision SUSY study at Hadron Colliders

We study the distribution of lepton pairs from the second lightest neutralino decay \tilde{\chi}^0_2-->\tilde{l}l followed by \tilde{l}\to \tilde{\chi}^0_1 l. The distribution of the ratio of lepton transverse momenta A_T shows peak structure if m_{ll}< m^{max}_{ll}/2 is required. The peak position A_T^{peak} is described by a simple function of the ino and slepton masses in the m_{ll}\sim 0 limit. When a moderate m_{ll} cut is applied, A_T^{peak} depends on the \tilde{\chi}^0_2 velocity distribution, but the dependence would be corrected by studying the lepton P_T distribution. A_T^{peak} and the edge of m_{ll} distributions are used to determine the mass parameters involved in the decay for parameters of interest to LHC experiments. For some cases the ino and slepton masses may be determined within 10% by the lepton distribution only independent of model assumptions. Correct combinations of A_{T}^{peak} and m_{ll}^{edge} would be identified even if different \tilde{\chi}^0_2 decay chains are co-existing. The analysis could be extended to the Tevatron energy scale or other cascade decays.Comment: 31 pages, 15 figure