NLO Event Simulation for Chargino Production at the ILC

We present an extension of the Monte Carlo Event Generator Whizard which includes chargino production at the ILC at NLO. We include photons using both a fixed order and a resummation approach. While the fixed order approach suffers from negative event weights, the resummation method solves this problem and automatically includes leading higher order corrections. We present results for cross sections and event generation for both methods and evaluate the systematic errors due to soft and collinear approximations. In the resummation approach, the residual uncertainty can be brought down to the per-mil level.Comment: 4 pages, 6 figures; submitted for the SUSY07 proceeding

Monte Carlo Simulations for NLO Chargino Production at the ILC

We present an extension of the Monte Carlo Event Generator Whizard which includes chargino production at the ILC at NLO. We include photons using both a fixed order and a resummation approach. In the latter, leading higher order corrections are automatically included. We present results for cross sections and event generation for both methods.Comment: 4 pages, 6 figures, to appear in the proceedings of the International Linear Collider Workshop LCWS07, Hamburg, 2007 v2: updated bibliography informatio

LHC Benchmark Scenarios for the Real Higgs Singlet Extension of the Standard Model

We present benchmark scenarios for searches for an additional Higgs state in the real Higgs singlet extension of the Standard Model in Run 2 of the LHC. The scenarios are selected such that they fulfill all relevant current theoretical and experimental constraints, but can potentially be discovered at the current LHC run. We take into account the results presented in earlier work and update the experimental constraints from relevant LHC Higgs searches and signal rate measurements. The benchmark scenarios are given separately for the low mass and high mass region, i.e. the mass range where the additional Higgs state is lighter or heavier than the discovered Higgs state at around 125 GeV. They have also been presented in the framework of the LHC Higgs Cross Section Working Group.Comment: 23 pages, 9 tables, 4 figures. arXiv admin note: text overlap with arXiv:1501.02234; v2: one subsection, one figure, and some references added, minor errors corrected. Corresponds to published journal versio

Constraining Extended Scalar Sectors at the LHC and beyond

We give a brief overview of beyond the Standard Model (BSM) theories with an extended scalar sector and their phenomenological status in the light of recent experimental results. We discuss the relevant theoretical and experimental constraints, and show their impact on the allowed parameter space of two specific models: the real scalar singlet extension of the Standard Model (SM) and the Inert Doublet Model. We emphasize the importance of the LHC measurements, both the direct searches for additional scalar bosons, as well as the precise measurements of properties of the Higgs boson of mass 125 GeV. We show the complementarity of these measurements to electroweak and dark matter observables.Comment: 18 pages, 8 figures; prepared for submission to MPLA (invited review) v2: several references and small text modification added to align with journal version. 2 small errors in plots correcte

Next-to-leading order predictions for WW+jet production

In this work we report on a next-to-leading order calculation of WW + jet production at hadron colliders, with subsequent leptonic decays of the W-bosons included. The calculation of the one-loop contributions is performed using generalized unitarity methods in order to derive analytic expressions for the relevant amplitudes. These amplitudes have been implemented in the parton-level Monte Carlo generator MCFM, which we use to provide a complete next-to-leading order calculation. Predictions for total cross-sections, as well as differential distributions for several key observables, are computed both for the LHC operating at 14 TeV as well as for a possible future 100 TeV proton-proton collider.Comment: 14 pages, 7 figures; v2: several references added, 2 typos corrected. Corresponds to published journal versio

Inert Doublet Model in light of LHC Run I and astrophysical data

We discuss the parameter space of the Inert Doublet Model, a two Higgs doublet model with a dark matter candidate. An extensive set of theoretical and experimental constraints on this model is considered, where both collider as well as astroparticle data limits, the latter in the form of dark matter relic density as well as direct detection, are taken into account. We discuss the effects of these constraints on the parameter space of the model. In particular, we do not require the IDM to provide the full dark matter content of the universe, which opens up additional regions in the parameter space accessible at collider experiments. The combination of all constraints leads to a relatively strong mass degeneracy in the dark scalar sector for masses < 200 GeV, and to a minimal scale ~ 45 GeV for the dark scalar masses. We also observe a stringent mass hierarchy MH > MA. We propose benchmark points and benchmark planes for dark scalar pair-production for the current LHC run being in compliance with all theoretical as well as experimental bounds.Comment: 29 pages, 19 figures; v2: 39 pages, 2 figures and tables added, references modified, title changed; corresponds to published journal versio