Prospects for charged Higgs searches at the LHC Akeroyd, A. G.; Aoki, M.; Arhrib, A. ...
The European physical journal. C, Particles and fields,
05/2017, Volume:
77, Issue:
5
Journal Article
Peer reviewed
Open access
The goal of this report is to summarize the current situation and discuss possible search strategies for charged scalars, in non-supersymmetric extensions of the Standard Model at the LHC. Such ...scalars appear in Multi-Higgs-Doublet models, in particular in the popular Two-Higgs-Doublet model, allowing for charged and additional neutral Higgs bosons. These models have the attractive property that electroweak precision observables are automatically in agreement with the Standard Model at the tree level. For the most popular version of this framework, Model II, a discovery of a charged Higgs boson remains challenging, since the parameter space is becoming very constrained, and the QCD background is very high. We also briefly comment on models with dark matter which constrain the corresponding charged scalars that occur in these models. The stakes of a possible discovery of an extended scalar sector are very high, and these searches should be pursued in all conceivable channels, at the LHC and at future colliders.
We consider the triple Higgs coupling for
h
(125) Higgs boson within the most general 2HDM. At moderate values of parameters of model, allowing by modern data, noticeable deviation of this coupling ...from its SM value is improbable. This deviation can be sizable only if some measurable parameters of the model are exotic.
The recent advances in 3‐D imaging of porous structures have generated a tremendous interest in the simulation of complex single and two‐phase flows. Lattice‐Boltzmann (LB) schemes present a powerful ...tool to solve the flow field directly from the binarized 3‐D images. However, as viscosity often plays an important role, the LB scheme should correctly treat viscosity effects. This is the case using a LB scheme with two relaxation times (TRT) unlike the broadly used, the single‐relaxation rate, BGK, where the velocity of the modeled fluid does not vary as the inverse of the viscosity applying the bounce‐back (no‐slip) boundary rule. The aim of this work is to apply the LB‐TRT approach to different types of porous media (straight channels, 2‐D model porous media, sandstone) to solve for the flow field and to evaluate the approach in terms of parameter dependence, error and convergence time on the basis of permeability. We show that the variation of permeability with the free relaxation parameter Λ of the TRT scheme depends on the heterogeneity of the sample and on the numerical resolution. The convergence time depends on the applied viscosity and the parameter standing for the speed of sound, thus the computation time can be reduced by choosing appropriate values of those parameters. Two approaches to calculate permeability (Darcy's law and viscous energy dissipation) are proposed and investigated. We recommend to use Darcy's law, as dependence on Λ is less important. Periodic (in the presence of a driving body force) and pressure boundary conditions are evaluated in terms of the results.
Key Points
Permeability K is confirmed to be viscosity independent using TRT LBM unlike BGK
K depends less on the numerical errors using Darcy's Law than Energy Dissipation
Computation time can be optimized by adjusting viscosity and sound speed
We find a set of necessary and sufficient conditions for the CP conservation in the most general 2HDM in terms of observable quantities. This set contains two simple and relatively easily testable ...conditions instead of the more complex conditions usually discussed.
We find a set of necessary and sufficient conditions for the CP conservation in the most general 2HDM in terms of observable quantities. This set contains two simple and relatively easily testable ...conditions instead of the more complex conditions usually discussed.
The values z of many observable quantities in the Nature are determined at some discrete set of times tn, separated by a small interval Δt (which may also represent a coordinate, etc.). Let the z ...value in neighbour point tn+1 = tn + Δt be expressed by the evolution equation as as z(tn+1) ≡ z(tn + Δt) = f(z(tn)). This equation gives a discrete description of phenomenon. Considering phenomena at t ≪ Δt this equation is transformed often into the differential equation allowing to determine z(t) leading to continuous description. It is usually assumed that the continuous description describes correctly the main features of a phenomenon at values t ≫ Δt. In this paper I show that the true behavior of some physical systems can differ strongly from that given by the continuous description. The observation of such effects may lead to the desire to supplement the original evolutionary model by additional mechanisms, the origin of which require special explanation. We will show that such construction may not be necessary - simple evolution model can describe properly different observable effects. This text contains no new calculations. Most of the discussed facts are well known. New is the treatment of the results.
This article proposes the use of the progressive web applications (PWA) for the geographic information systems' (GIS) web user interfaces. The main advantages of this approach for GIS: use of ...arbitrary mobile and stationary devices; work in conditions of unstable connection to GIS server with fault-tolerant user input data delivery to the server, when the connection is restored; work offline with the information stored on client device, when the server is disconnected, and automatic synchronization of changed data, when the server connection is active; network traffic savings during data transfer. The above mentioned advantages are important for a number of practical applications in cadastral accounting and construction.
Recently CMS and ATLAS announced that they had measured the Higgs boson parity. In this note we show that their approach can determine this parity only under the additional assumption that an ...extension of Standard Model of some special type is realized in Nature. We show that the used approach gives no information about the Higgs boson parity when assuming most other extensions of the Standard Model.
In general, explicit numerical schemes are only conditionally stable. A particularity of lattice Boltzmann multiple-relaxation-time (MRT) schemes is the presence of free (“kinetic”) relaxation ...parameters. They do not appear in the transport coefficients of the modelled second-order (macroscopic) equations but they have an impact on the effective accuracy and stability of the algorithm. The simplest uniform choice (the well known BGK/SRT model) is often inadequate, and therefore a compromise in the complexity of the model is sought. For this purpose, the von Neumann stability analysis is performed for the d1Q3 two-relaxation-time (TRT) advection–diffusion model. The extended optimal (EOTRT) model, which relates the two collision times such that the most stable scheme is set by a suitable choice of the equilibrium parameters, equal for any Peclet number, is then developed. This extends the very recently derived optimal subclass (OTRT) to larger combinations of “physical” and “kinetic” collision rates. Next, we provide the necessary and/or sufficient stability limits on the EOTRT subclass for a wide range of velocity sets, with and without numerical diffusion, and delineate the interesting choices of free equilibrium weights for the d2Q9 and d3Q15 models. The BGK/SRT model is without advanced advection properties; we prove (for minimal stencil schemes d1Q3, d2Q5 and d3Q7) that the non-negativity of the equilibrium distribution is necessary for its stability in the advection-dominated limit. Beyond the EOTRT and BGK/SRT subclasses of the TRT model, blind choices of the “ghost” collision number may result in quite unstable schemes, even for positive equilibrium. However, we find that the d1Q3 stability curves govern the advection properties of the multi-dimensional models and a fuller picture of the TRT stability properties begins to emerge.
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