If the Standard Model (SM) of particle interactions is extended to include a second scalar doublet, which is odd under an unbroken Z 2 discrete symmetry, it may be called the dark scalar doublet, because its lightest neutral member, say H 0 , is one posssible component for the dark matter of the Universe. We discuss the general phenomenology of the four particles of this doublet, without assuming that H 0 is the dominant source of dark matter. We also consider the impact of this dark scalar doublet on the phenomenology of the SM Higgs boson h.

This report summarises the physics opportunities for the study of Higgs bosons and the dynamics of electroweak symmetry breaking at the 100 TeV pp collider.

We present a study of the t-channel mode of single top quark production at the upgraded Tevatron pp collider, including the next-to-leading order (NLO) QCD corrections to the production and the decay of a single top quark. The narrow width approximation was adopted in order to preserve the spin of the top quark in its production and decay. We discuss the effects of different O(α s ) contributions on the inclusive cross section as well as various kinematic distributions after imposing the relevant cuts to select t-channel single top signal events.

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We adopt a Markov chain Monte Carlo method to examine various new physics models which can generate the forward-backward asymmetry in top quark pair production observed at the Tevatron by the CDF Collaboration. We study the following new physics models: (1) exotic gluon G 0 , (2) extra Z 0 boson with flavor-conserving interaction, (3) extra Z 0 with flavor-violating u-t-Z 0 interaction, (4) extra W 0 with flavor-violating d-t-W 0 interaction, and (5) extra scalars S and S AE with flavor-violating u-t-S and d-t-S AE interactions. After combining the forward-backward asymmetry with the measurement of the top pair production cross section and the t " t invariant mass distribution at the Tevatron, we find that an axial vector exotic gluon G 0 of mass about 1 TeV or 2 TeV or a W 0 of mass about 2TeV offer an improvement over the standard model. The other models considered do not fit the data significantly better than the standard model. We also emphasize a few points that have been long ignored in the literature for new physics searches: (1) heavy resonance width effects, (2) renormalization scale dependence, and (3) next-to-leading order corrections to the t " t invariant mass spectrum. We argue that these three effects are crucial to test or exclude new physics effects in the top quark pair asymmetry.

We present a study of s-channel single top quark production at the upgraded Tevatron pp collider, including the next-to-leading order (NLO) QCD corrections to the production and decay of the top quark. The "modified" narrow width approximation was adopted to preserve the spin of the top quark in its production and decay. We discuss the effect of the different O(α s ) contributions on the inclusive cross section as well as various kinematical distributions after imposing the relevant cuts to select s-channel single top signal events. In particular the O(α s ) decay contribution, while small in size, has a significant impact on several distributions. With the help of the best-jet algorithm to reconstruct the top quark we demonstrate that it is possible to study kinematical and spin correlations in s-channel single top events. We furthermore compare top quark spin measurements in two different basis and show how NLO corrections have to be taken into consideration in searches for the Higgs boson through W ± H associated production at the Tevatron.

In the minimal supersymmetric standard model ͑MSSM͒, the masses of the charged Higgs boson (H Ϯ ) and the CP-odd scalar ͑A͒ are related by M H ϩ 2 ϭM A 2 ϩm W 2 at the Born level. Because the coupling of W Ϫ -A-H ϩ is fixed by the gauge interaction, the Born level production rate of qq Ј→W Ϯ *→AH Ϯ depends on only one supersymmetry parameter-the mass (M A ) of A. We examine the sensitivity of the CERN LHC to this signal event in the A(→bb )H ϩ (→ ϩ ) and A(→bb )H ϩ (→tb ) decay channels. We illustrate how to test the mass relation between A and H ϩ in case the signal is found. If the signal is not found, the product of the decay branching ratios of A and H Ϯ predicted by the MSSM is bounded from above as a function of M A .

The successful operation of the Large Hadron Collider (LHC) and the excellent performance of the ATLAS, CMS, LHCb and ALICE detectors in Run-1 and Run-2 with pp collisions at center-of-mass energies of 7, 8 and 13 TeV as well as the giant leap in precision calculations and modeling of fundamental interactions at hadron colliders have allowed an extraordinary breadth of physics studies including precision measurements of a variety physics processes. The LHC results have so far confirmed the validity of the Standard Model of particle physics up to unprecedented energy scales and with great precision in the sectors of strong and electroweak interactions as well as flavour physics, for instance in top quark physics. The upgrade of the LHC to a High Luminosity phase (HL-LHC) at 14 TeV center-of-mass energy with 3 ab −1 of integrated luminosity will probe the Standard Model with even greater precision and will extend the sensitivity to possible anomalies in the Standard Model, thanks to a ten-fold larger data set, upgraded detectors and expected improvements in the theoretical understanding. This document summarises the physics reach of the HL-LHC in the realm of strong and electroweak interactions and top quark physics, and provides a glimpse of the potential of a possible further upgrade of the LHC to a 27 TeV pp collider, the High-Energy LHC (HE-LHC), assumed to accumulate an integrated luminosity of 15 ab −1 .