Search

In the framework of the left-right twin Higgs (LRTH) model, we investigate the single top partner production at lepton colliders. We calculate the production cross-sections of the processes , and at TeV, and display some typical differential distributions of the final state particles. [ABSTRACT FROM AUTHOR]

The discovery of the Higgs particle at 125 GeV is demanding a detailed knowledge of the properties of this fundamental component of the Standard Model. To that aim various proposals of electron and muon colliders have been put forward for precision studies of the partial widths of the various decay channels. It is shown that in the case of a Higgs factory through a muon collider, sizeable radiative effects - of order of 50% - must be carefully taken into account for a precise measurement of the leptonic and total widths of the Higgs particle. Similar effects do not apply in the case of Higgs production in electron-positron colliders. [ABSTRACT FROM AUTHOR]

We calculate the complete next-to-leading order (NLO) QCD corrections to the -odd mirror quark pair , , , production in the littlest Higgs model with -parity (LHT) at a high energy collider. We present the dependence of the leading order (LO) and NLO QCD corrected cross sections on the colliding energy . Our calculation includes the subsequent full weak decays of the final -odd mirror quarks by adopting the narrow width approximation and the exclusive 2-jet event selection criterion. We provide the LO and QCD NLO kinematic distributions of final particles. We find that the NLO QCD correction is phase space dependent and modifies the LO cross section evidently. The -factor increases noticeably when approaches the threshold of the on-shell -pair production. We conclude that it is possible to separate the signature of the -odd quark pair production from possible Standard Model (SM) background by taking proper kinematic cut. [ABSTRACT FROM AUTHOR]

A warped extra dimension model predicts an extra scalar particle beyond the Standard Model (SM) which is called a radion. Although interactions of the radion are similar to those of the Higgs boson in the SM, a relatively light radion (< 100 GeV) is not severely constrained from the Higgs search experiments at the LHC. In this paper we study discovery potential of the radion at a photon collider as an option of ILC. Owing to the trace anomaly of the energy-momentum tensor, both a production of radion in 7 7 collision and its decay to gluon pair are enhanced sizably. We find that the photon collider has a sensitivity for discovering the radion in low-mass region up to Aw, ~ 3 TeV, where A, is a scale parameter which suppresses the interactions of radion to the SM particles. [ABSTRACT FROM AUTHOR]

We review the No-Scale ℱ-SU(5) model with extra TeV-scale vector-like flippon multiplets and its associated collider phenomenology in the search for supersymmetry at the LHC. The model framework possesses the rather unique capacity to provide a light CP-even Higgs boson mass in the favored 124-126 GeV window while simultaneously retaining a testably light SUSY spectrum that is consistent with emerging low-statistics excesses beyond the Standard Model expectation in the ATLAS and CMS multijet data. [ABSTRACT FROM AUTHOR]

Decays of B mesons into final states containing a τ lepton are sensitive to new charged current interactions that break lepton-flavor universality. These decays have been studied only at e+e- colliders, where the low-background environment and well-known initial state make it possible to observe small signals with undetectable neutrinos. In particular, the large data samples of the B factories and recent advances in techniques for full-event reconstruction have led to evidence for the decay B+→τ+ ντ and unambiguous observation of the decays . These results exclude large regions of the parameter space for a variety of new physics models. Furthermore, the branching fraction for has been measured to be higher than the Standard Model expectation by more than three standard deviations, making this an interesting topic for further research. This paper reviews the theoretical and experimental status of this topic, summarizing the results at this time and outlining the path for further improvements. [ABSTRACT FROM AUTHOR]

An overview is given on key physics, detector and accelerator aspects of the LHeC including its further development with emphasis to its role as the cleanest microscope of parton dynamics and a precision Higgs facility. [ABSTRACT FROM AUTHOR]

We review non-Standard Model Higgs signatures which are missed in standard analyses by both ATLAS and CMS and show how the strong bounds by recent measurements can be relaxed in strongly-interacting theories. We also review strategies how to measure or constrain exotic Higgs decay at the LHC and a future linear collider. [ABSTRACT FROM AUTHOR]

The left–right twin Higgs (LRTH) model predicts the existence of the new neutral gauge boson Z′. In this paper, we calculate the contributions of this new particle to the processes e+e-→l+l-, $b\bar b$ and $c\bar c$ and study the possibility of detecting this new particle via these processes in the future high-energy linear e+e- collider (LC) experiments with $\sqrt{s}=500~{\rm GeV}$ and £int = 340 fb-1, both for unpolarized and polarized beams. We find that the new gauge boson Z′ is most sensitive to the process $e^{+}e^{-}\rightarrow c\bar{c}$ with suitably polarized beams. As long as MZ′ ≤ 1.9 TeV, the absolute value of the relative correction parameter is larger than 5%. We calculate the forward–backward asymmetries for the process $e^{+}e^{-}\rightarrow f\bar{f}$, the results show that the possible signals of Z′ might be detected via measuring the deviations of AFB from its SM prediction for $\sqrt{s}\simeq M_{Z'}$. Bounds on Z′ masses are also estimated within 95% confidence level. From our analysis, we conclude that the new gauge boson is most sensitive to the process F>$e^+e^-\to c\bar c$ and its virtual effects are most easy to be observed via this process in the future LC experiments. [ABSTRACT FROM AUTHOR]

We update the upper bound on the lightest CP-even Higgs mass in the NMSSM, which is given as a function of tan β and λ. It is pointed out that large values of tan β, with λ not too small, imply a large value for the MSSM-like parameter MA. We include the available one- and two-loop corrections to the NMSSM Higgs masses, and constraints from the absence of Landau singularities below the GUT scale as well as from the stability of the NMSSM Higgs potential. For mtop varying between 171.4 and 178 GeV, squark masses of 1 TeV and maximal mixing the upper bound is assumed near tan β ~ 2 and varies between 139.9 and 141.4 GeV. [ABSTRACT FROM AUTHOR]

We review the present status of the QCD corrected cross-sections and kinematic distributions for the production of a Higgs boson in association with bottom quarks at the Fermilab Tevatron and CERN Large Hadron Collider. Results are presented for the Minimal Supersymmetric Standard Model where, for large tan β, these production modes can be greatly enhanced compared to the Standard Model case. The next-to-leading order QCD results are much less sensitive to the renormalization and factorization scales than the lowest order results, but have a significant dependence on the choice of the renormalization scheme for the bottom quark Yukawa coupling. We also investigate the uncertainties coming from the Parton Distribution Functions and find that these uncertainties can be comparable to the uncertainties from the remaining scale dependence of the next-to-leading order results. We present results separately for the different final states depending on the number of bottom quarks identified. [ABSTRACT FROM AUTHOR]

We have studied a top-Higgs production process $e^{+}e^{-}\rightarrow t\bar{c}h_{t}^{0}$ in the topcolor assisted technicolor (TC2) model. The studies show that the production cross-section of $e^{+}e^{-}\rightarrow t\bar{c}h_{t}^{0}$ is at the order of magnitude 10 fb in reasonable parameters space of TC2 model. A few hundred events of top-Higgs can be produced each year at the high energy linear e+e- colliders (LC). The top-Higgs may be directly observed via this process. [ABSTRACT FROM AUTHOR]

In this work, we address the phenomenological consequences of explicit CP violation on direct Higgs-boson searches at high energy colliders. Having a restricted parameter space, we concentrate on the recently proposed gluino-axion model, and investigate the CP violation capability of the model subject to the recent experimental data. It is shown that the Higgs masses as well as their CP compositions are quite sensitive to the supersymmetric CP phases. The lightest Higgs is found to be nearly CP even to a good approximation whilst the remaining two heavy scalars do not have definite CP parities. [ABSTRACT FROM AUTHOR]