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Different production processes involving the Higgs boson, such as annihilation and W/Z boson fusion, will be observed in the International Linear Collider (ILC). The ILC operates at a center-of-mass (CM) energy of s = 2 0 0 –1000 GeV. The study reveals that the production cross-section can either be enhanced or reduced depending on the CM energy and the specific combination used, which has implications for selecting appropriate production processes. Additionally, this investigation highlights that by polarizing beams, the number of measurable observables increases. These observables, such as left–right asymmetry, detailed effective polarization, and adequate effective luminosity, are crucial to ascertain contemporary physical parameters in physics models absurdly the Standard Model (SM). [ABSTRACT FROM AUTHOR]

Supersymmetric extensions of the Standard Model have been in vogue for over half a century. They have many interesting theoretical properties like calculability, absence of quadratic divergences, and phenomenologically impactful features like gauge coupling unification, dark matter candidates, signatures at present and future colliders, etc. A defining feature of these models is the calculability of Higgs mass in terms of a few parameters. The discovery of a Higgs particle with a mass of around 125 GeV thus has significant implications. The null results for the searches of superpartners at LHC have also put further constraints. Taken together with direct detection limits on weakly interacting massive particle dark matter, it appears that TeV scale supersymmetry is not realized in Nature, and the theoretical expectations have reached a turning point. The present onslaught from the experiments suggests that supersymmetric models need a more complex particle structure, Lagrangian and breaking patterns to be a natural solution to the hierarchy problem. We review existing models and discuss their feasibility in the current and future experimental programs. [ABSTRACT FROM AUTHOR]

A brief review of phenomenological analyses involving colliders, precision tests, flavor physics and dark matter is given considering nonholomorphic soft supersymmetry breaking interactions within the MSSM framework. [ABSTRACT FROM AUTHOR]

A search is performed for neutral non-standard-model Higgs bosons decaying to two muons in the context of the minimal supersymmetric standard model (MSSM). Proton-proton collision data recorded by the CMS experiment at the CERN Large Hadron Collider at a center-of-mass energy of 13TeVwere used, corresponding to an integrated luminosity of 35.9fb-1. The search is sensitive to neutral Higgs bosons produced via the gluon fusion process or in association with a bbquark pair. No significant deviations from the standard model expectation are observed. Upper limits at 95% confidence level are set in the context of the mmod+hand phenomenological MSSM scenarios on the parameter tanβas a function of the mass of the pseudoscalar Aboson, in the range from 130 to 600GeV. The results are also used to set a model-independent limit on the product of the branching fraction for the decay into a muon pair and the cross section for the production of a scalar neutral boson, either via gluon fusion, or in association with bquarks, in the mass range from 130 to 1000GeV.

A search is performed for neutral non-standard-model Higgs bosons decaying to two muons in the context of the minimal supersymmetric standard model (MSSM). Proton-proton collision data recorded by the CMS experiment at the CERN Large Hadron Collider at a center-of-mass energy of 13TeVwere used, corresponding to an integrated luminosity of 35.9fb-1. The search is sensitive to neutral Higgs bosons produced via the gluon fusion process or in association with a bbquark pair. No significant deviations from the standard model expectation are observed. Upper limits at 95% confidence level are set in the context of the mmod+hand phenomenological MSSM scenarios on the parameter tanβas a function of the mass of the pseudoscalar Aboson, in the range from 130 to 600GeV. The results are also used to set a model-independent limit on the product of the branching fraction for the decay into a muon pair and the cross section for the production of a scalar neutral boson, either via gluon fusion, or in association with bquarks, in the mass range from 130 to 1000GeV.

In this paper, a study of four different machine learning (ML) algorithms is performed to determine the most suitable ML technique to disentangle a hypothetical supersymmetry (SUSY) signal from its corresponding Standard Model (SM) backgrounds and to establish their impact on signal significance. The study focuses on the production of SUSY top squark pairs (stops), in the mass range of 5 0 0 < m t ̃ 1 < 8 0 0 GeV, from proton–proton collisions with a center of mass energy of 13 TeV and an integrated luminosity of 1 4 0 fb − 1 , emulating the data-taking conditions of the run II Large Hadron Collider (LHC) accelerator. In particular, the semileptonic channel is analyzed, corresponding to final states with a single isolated lepton (electron or muon), missing transverse energy, and four jets, with at least one tagged as b -jet. The challenging compressed spectra region is targeted, where the stop decays mainly into a W boson, a b -jet, and a neutralino ( t ̃ 1 → W + b + χ ̃ 1 0 ), with a mass gap between the stop and the neutralino of about 150 GeV. The ML algorithms are chosen to cover different mathematical implementations and features in ML. We compare the performance of a logistic regression (LR), a Random Forest (RF), an eXtreme Gradient Boosting, XGboost (XG) and a Neural Network (NN) algorithm. Our results indicate that XG and NN classifiers provide the highest improvements (over 17%) in signal significance, when compared to a standard analysis method based on sequential requirements of different kinematic variables. The improvement in signal significance provided by the NN increases up to 31% for the highest stop mass considered in this study (800 GeV). The RF algorithm presents a smaller improvement that decreases with stop mass. On the other hand, the LR algorithm shows the worst performance in signal significance which even does not compete with the results obtained by an optimized cut and count method. [ABSTRACT FROM AUTHOR]

Supersymmetry is a well-motivated theory for physics beyond the Standard Model. In particular, supersymmetric models can naturally possess dark matter candidates that can give rise to the measured dark matter content of the universe. We review several models that have been analyzed with regard to dark matter by groups based in Spain in recent years. These models include, in particular, the Minimal Supersymmetric Standard Model (MSSM) and the ' μ from ν ' Supersymmetric Standard Model ( μ ν SSM) in various versions. [ABSTRACT FROM AUTHOR]

We propose a new neutrino flavor model based on a D 4 × U (1) flavor symmetry providing predictions for neutrino masses and mixing along with a successful generation of the observed Baryon Asymmetry of the Universe (BAU). After the spontaneous breaking of the flavor symmetry, the type I seesaw mechanism leads to a light neutrino mass matrix with broken μ − τ symmetry. By performing a numerical analysis, we find that the model favors a normal mass hierarchy with the lightest neutrino mass lies in the range m 1 ∈ [ 2. 516 , 21. 351 ] meV. The phenomenological implications of the neutrino sector are explored in detail and the results are discussed. Moreover, the generation of BAU is addressed via the leptogenesis mechanism from the decay of three right-handed neutrinos N i. Through analytical and numerical analysis of the baryon asymmetry parameter Y B , a successful unflavored leptogenesis takes place within the allowed parameter space obtained from neutrino phenomenology. We also examine interesting correlations between Y B and low energy observables and provide a comprehensive discussion of the results. [ABSTRACT FROM AUTHOR]

The objective of this study is to correlate the scaling factor of the Standard Model (SM) like Higgs boson and the cross section ratio of the process e + e − → h h f f ¯ where f≠t, normalized to SM predictions in the type I of the Two Higgs Doublet Model. All calculations have been performed at s = 500 GeV and 1 ≤ tan β ≤ 30 for masses m H = m A = m H ± = 300 G e V and mH = 300 GeV, m A = m H ± = 500 GeV. The working scenario is by taking without alignment limit, that is sβ−α = 0.98 and sβ−α = 0.99, 0.995, which gives the enhancement in the cross section, particularly a few times greater than the predictions of the SM due to resonant-impacts of the additional heavy neutral Higgs bosons. This shows that enhancement in cross section occurs on leaving the alignment i.e., sβ−α = 1, at which all the higgs that couple to vector bosons and fermions have the same values as in SM at tree level. A large value of enhancement factor is obtained at sβ−α = 0.98 as compared to sβ−α = 0.99, 0.995. Furthermore, the decrease in the enhancement factor is observed for the case when mH = 300 GeV, m A = m H ± = 500 GeV. The behavior of the scaling factor with tan β is also studied, which shows that for large values of tan β , the scaling factor becomes equal to sβ−α. Finally a convincing correlation is achieved by taking into account, the experimental and theoretical constraints e.g, perturbative unitarity, vacuum stability and electroweak oblique parameters. [ABSTRACT FROM AUTHOR]

Supersymmetry is a well-motivated theory for physics beyond the Standard Model. In particular, supersymmetric models can naturally possess dark matter candidates that can give rise to the measured dark matter content of the universe. We review several models that have been analyzed with regard to dark matter by groups based in Spain in recent years. These models include, in particular, the Minimal Supersymmetric Standard Model (MSSM) and the ‘μ from ν’ Supersymmetric Standard Model (μνSSM) in various versions.

Single top quark production through weak interactions is considered to be an important source of charged Higgs in the Minimal Super Symmetric Standard Model.In the s-channel single top production having largest cross-section may appear as a propagator in the form of heavy resonance state decaying to a pair of top and bottom quark. The process under investigation is p p → H ± → t b → b b ̄ W ± → b b ̄ τ ± ν τ , where top quark exclusively decays into a pair of bottom quark and W boson while W boson subsequently decays to τ jet and neutrino. So the final state is characterized by the presence of two b jets, hadronic τ decay and missing transverse energy. Within the presence of QCD multijet and electroweak background events at LHC, it has been demonstrated that the charged Higgs signal observability is possible within the available MSSM parameter space (tanβ, m H ± ) respecting all experimental and theoretical constraints. In order to show the observability potential of charged Higgs, the exclusion curves at 95% confidence level and 5σ contours are plotted at different integrated luminosities with s = 14 TeV. [ABSTRACT FROM AUTHOR]

A search for neutral Higgs bosons decaying to pairs of τ leptons with the ATLAS detector at the LHC is presented. The analysis is based on proton-proton collisions at a center-of-mass energy of 7 TeV, recorded in 2010 and corresponding to an integrated luminosity of 36 pb-1. After signal selection, 276 events are observed in this data sample. The observed number of events is consistent with the total expected background of 269±36 events. Exclusion limits at the 95% confidence level are derived for the production cross section of a generic Higgs boson φ as a function of the Higgs boson mass and for A/H/h production in the Minimal Supersymmetric Standard Model (MSSM) as a function of the parameters mA and tanβ. © 2011 CERN.

We determine the anomaly free discrete R symmetries, consistent with the MSSM, that commute with SU(5) and suppress the μ parameter and nucleon decay. We show that the order M of such Z{double-struck}MR symmetries has to divide 24 and identify 5 viable symmetries. The simplest possibility is a Z{double-struck}4R symmetry which commutes with SO(10). We present a string-derived model with this Z{double-struck}4R symmetry and the exact MSSM spectrum below the GUT scale; in this model Z{double-struck}4R originates from the Lorentz symmetry of compactified dimensions. We extend the discussion to include the singlet extensions of the MSSM and find Z{double-struck}4R and Z{double-struck}8Rare the only possible symmetries capable of solving the μ problem in the NMSSM. We also show that a singlet extension of the MSSM based on a Z{double-struck}24Rsymmetry can provide a simultaneous solution to the μ and strong CP problem with the axion coupling in the favoured window. © 2011 Elsevier B.V.

Recently it was shown that there is a unique Z4R symmetry for the MSSM which allows for the Yukawa couplings and dimension five neutrino mass operator, forbids the μ term and commutes with SO(10). This Z4R symmetry contains matter parity as a subgroup and forbids dimension four and five proton decay operators. We show how to construct string vacua with discrete R symmetries in general and this symmetry in particular, and present an explicit example which exhibits the exact MSSM spectrum, the Z4R symmetry as well as other desired features such as gauge-top unification. We introduce the Hilbert basis method for determining all D-flat configurations and efficient algorithms for identifying field configurations with a desired residual symmetry. These methods are used in an explicit example, in which we describe in detail how to construct a supersymmetric vacuum configuration with the phenomenologically attractive Z4R symmetry. At the perturbative level, this is a supersymmetric Minkowski vacuum in which almost all singlet fields (moduli) are fixed. © 2011 Elsevier B.V.

We discuss the possibility of light dark matter in a general singlet extension of the MSSM. Singlino LSPs with masses of a few GeV can explain the signals reported by the CRESST, CoGeNT and possibly also DAMA experiments. The interactions between singlinos and nuclei are mediated by a scalar whose properties coincide with those of the SM Higgs up to two crucial differences: the scalar has a mass of a few GeV and its interaction strengths are suppressed by a universal factor. We show that such a scalar can be consistent with current experimental constraints, and that annihilation of singlinos into such scalars in the early universe can naturally lead to a relic abundance consistent with the observed density of cold dark matter. © 2010 Elsevier B.V.

We consider the possible anomaly free Abelian discrete symmetries of the MSSM that forbid the μ-term at perturbative order. Allowing for anomaly cancellation via the Green-Schwarz mechanism we identify discrete R-symmetries as the only possibility and prove that there is a unique Z4R symmetry that commutes with SO(10). We argue that non-perturbative effects will generate a μ-term of electroweak order thus solving the μ-problem. The non-perturbative effects break the Z4R symmetry leaving an exact Z2 matter parity. As a result dimension four baryon- and lepton-number violating operators are absent while, at the non-perturbative level, dimension five baryon- and lepton-number violating operators get induced but are highly suppressed so that the nucleon decay rate is well within present bounds. © 2010 Elsevier B.V.

We consider the possible anomaly free Abelian discrete symmetries of the MSSM that forbid the μ-term at perturbative order. Allowing for anomaly cancellation via the Green-Schwarz mechanism we identify discrete R-symmetries as the only possibility and prove that there is a unique Z4R symmetry that commutes with SO(10). We argue that non-perturbative effects will generate a μ-term of electroweak order thus solving the μ-problem. The non-perturbative effects break the Z4R symmetry leaving an exact Z2 matter parity. As a result dimension four baryon- and lepton-number violating operators are absent while, at the non-perturbative level, dimension five baryon- and lepton-number violating operators get induced but are highly suppressed so that the nucleon decay rate is well within present bounds. © 2010 Elsevier B.V.

We discuss the possibility of light dark matter in a general singlet extension of the MSSM. Singlino LSPs with masses of a few GeV can explain the signals reported by the CRESST, CoGeNT and possibly also DAMA experiments. The interactions between singlinos and nuclei are mediated by a scalar whose properties coincide with those of the SM Higgs up to two crucial differences: the scalar has a mass of a few GeV and its interaction strengths are suppressed by a universal factor. We show that such a scalar can be consistent with current experimental constraints, and that annihilation of singlinos into such scalars in the early universe can naturally lead to a relic abundance consistent with the observed density of cold dark matter. © 2010 Elsevier B.V.

A search for neutral Higgs bosons decaying to pairs of τ leptons with the ATLAS detector at the LHC is presented. The analysis is based on proton-proton collisions at a center-of-mass energy of 7 TeV, recorded in 2010 and corresponding to an integrated luminosity of 36 pb-1. After signal selection, 276 events are observed in this data sample. The observed number of events is consistent with the total expected background of 269±36 events. Exclusion limits at the 95% confidence level are derived for the production cross section of a generic Higgs boson φ as a function of the Higgs boson mass and for A/H/h production in the Minimal Supersymmetric Standard Model (MSSM) as a function of the parameters mA and tanβ. © 2011 CERN.

We perform a comprehensive global analysis in the Minimal Supersymmetric Standard Model (MSSM) as well as in the 2-Higgs Doublet Model (2HDM) of the production and decay mechanisms of charged Higgs bosons (H±) at the Large Hadron Collider (LHC). We start from accounting for the most recent experimental results (SM-like Higgs boson signal strengths and search limits for new Higgs boson states obtained at Run-1 and -2 of the LHC and previous colliders), from (both direct and indirect) searches for supersymmetric particles as well as from flavor observables (from both e+e− factories and hadron colliders). We then present precise predictions for H± cross sections and decay rates in different reference scenarios of the two aforementioned models in terms of the parameter space currently available, specifically, mapped over the customary (mA,H±,tanβ) planes. These include the mhmod+ and hMSSM configurations of the MSSM and the 2HDM Type-I, -II, -X, and -Y for which we also enforce theoretical constraints, such as vacuum stability, perturbativity, and unitarity. We also define specific Benchmark Points (BPs) which are always close to (or coinciding with) the best fits of the theoretical scenarios to experimental data. We finally briefly discuss the ensuing phenomenology for the purpose of aiding future searches for such charged Higgs boson states.

Extended scalar sectors appear in various extensions of the Standard Model of particle physics, such as supersymmetric models. They are also generic extensions of the Standard Model and can address a number of its shortcomings. Direct searches for additional Higgs bosons and measurements of the 125-GeV Higgs boson, both of which provide insights into the different possible sectors, are carried out at the LHC. This review gives an overview of searches for the additional Higgs bosons and their implications for different models. The discussed analyses comprise searches for neutral and charged Higgs bosons that decay in various final states. In addition, the review summarizes the constraints from precision measurements, including in particular the observed couplings of the 125-GeV Higgs boson. While several models naturally incorporate a Higgs boson with couplings that are similar to the ones in the Standard Model, the measurements of the 125-GeV Higgs boson provide constraints on all considered extensions. [ABSTRACT FROM AUTHOR]

Studying the properties of the Higgs boson can be an important window to explore the physics beyond the Standard Model (SM). In this work, we present studies on the implications of the Higgs precision measurements at future Higgs Factories. We perform a global fit to various Higgs search channels to obtain the 95% C.L. constraints on the model parameter spaces of two-Higgs Doublet Model (2HDM) and Minimal Supersymmetric Standard Model (MSSM). In the 2HDM, we analyze tree-level effects as well as one-loop contributions from the heavy Higgs bosons. The strong constraints on cos (β − α) , heavy Higgs masses and their mass splitting are complementary to direct search of the LHC as well as possible future Z pole precision measurements. For the MSSM, we study both the Higgs couplings and mass precisions. The constraints on the CP-odd Higgs mass m A and stop mass scale m SUSY can be complementary to the direct search of HL-LHC. We also compare the sensitivity of various future Higgs factories, namely, Circular Electron Positron Collider (CEPC), Future Circular Collider (FCC)-ee and International Linear Collider (ILC). [ABSTRACT FROM AUTHOR]

We analyze the one-loop correction to Z → ν ν decay in framework of Minimal R-symmetric Supersymmetric Standard Model (MRSSM) in detail with normal and inverse neutrino mass orderings, as a function of tan β , Dirac mass parameters M D W and μ u (μ d) , slepton mass m l that parametrize the mass matrices. The numerical results indicate that the branching ratio for Z → ν ν decay is compatible with the experimental measurement and the SM expectation at 2 σ level. For inverse neutrino mass ordering, the prediction exceeds the SM expectation at 1 σ level. The prediction on Br (Z → ν ν) increases proportionally to tan β and inversely proportionally to m l . For normal neutrino mass ordering, the peak value of the prediction on Br (Z → ν ν) exceeds the SM expectation at 1 σ level. [ABSTRACT FROM AUTHOR]

We explored a Higgs inflationary scenario in the SUGRA embedding of the MSSM in Einstein frame where the inflaton is contained in the SU(2) Higgs doublet. We include all higher order non-renormalizable terms to the MSSM superpotential and an appropriate Kähler potential which can provide slow-roll inflaton potential in the D-flat direction. In this model, a plateau-like inflation potential can be obtained if the imaginary part of the neutral Higgs acts as the inflaton. The inflationary predictions of this model are consistent with the latest CMB observations. The model represents a successful Higgs inflation scenario in the context of Supergravity and it is compatible with Minimal Supersymmetric extension of the Standard Model.

A search for neutral Higgs bosons predicted in the minimal supersymmetric standard model (MSSM) for μ+μ− decay channels is presented. The analysis uses data collected by the CMS experiment at the LHC in proton–proton collisions at centre-of-mass energies of 7 and 8 TeV, corresponding to integrated luminosities of 5.1 and 19.3 fb−1, respectively. The search is sensitive to Higgs bosons produced either through the gluon fusion process or in association with a bb‾ quark pair. No statistically significant excess is observed in the μ+μ− mass spectrum. Results are interpreted in the framework of several benchmark scenarios, and the data are used to set an upper limit on the MSSM parameter tan⁡β as a function of the mass of the pseudoscalar A boson in the range from 115 to 300 GeV. Model independent upper limits are given for the product of the cross section and branching fraction for gluon fusion and b quark associated production at s=8 TeV. They are the most stringent limits obtained to date in this channel.

Results are reported on a search for decays of a pseudoscalar A boson into a Z boson and a light scalar h boson, where the Z boson decays into a pair of oppositely-charged electrons or muons, and the h boson decays into bb‾. The search is based on data from proton–proton collisions at a center-of-mass energy s=8 TeV collected with the CMS detector, corresponding to an integrated luminosity of 19.7 fb−1. The h boson is assumed to be the standard model-like Higgs boson with a mass of 125 GeV. With no evidence for signal, upper limits are obtained on the product of the production cross section and the branching fraction of the A boson in the Zh channel. Results are also interpreted in the context of two Higgs doublet models.

Achieving high accuracy has become a key design objective in high quantity digital data computing devices. To enhance the accuracy, a high performance Modified Static Segment approximate Multiplier (MSSM) is proposed in this paper. It increases the accuracy based on the negating lower order significant information of input operands using Significance Estimator Logic Circuit (SELC). The performance of proposed MSSM is compared with the existing approximate multipliers such as a Dynamic Segment approximate Multiplier (DSM) and Static Segment approximate Multiplier (SSM) for all input combinations. These multipliers are implemented and simulated using Xilinx 14.2 ISE. In MSSM method, 99% of average computational accuracy can be achieved for a 16-bit multiplication even with an 8 × 8-bit multiplier from all combinations of input operands instead of 95% of average computational accuracy from 61% of input operand pair in the existing SSM method. The proposed 16-bit MSSM offers a savings of 83.45% LUTs, 38.78% power and it exhibits 24.40% less delay, 0.6% less computational accuracy than the existing DSM. [ABSTRACT FROM AUTHOR]