Search for Physics Beyond the Standard Model in Events with High-Momentum Higgs Bosons and Missing Transverse Momentum in Proton-Proton Collisions at 13 TeV
Not Available
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
SEARCH · Search NASA
Results for “HIGGS MODEL”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Expected Precision of Higgs Boson Partial Widths within the Standard Model
Abstract Not Provided
Lattice, Phenomenology-HEP,HEPEX, HEPTH↗
Expected Precision of Higgs Boson Partial Widths within the Standard Model
Abstract Not Provided
Lepage, G. Peter↗
Higgs Bosons in Non-Minimal Supersymmetric Model
Explore the source record for details and available documents.
Ellis, J.↗
Search for direct production of electroweakinos in final states with one lepton, missing transverse momentum and a Higgs boson decaying into two b -jets in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector
The results of a search for electroweakino pair production $pp \rightarrow \tilde\chi^\pm_1 \tilde\chi^0_2$ in which the chargino ($\tilde\chi^\pm_1$) decays into a $W$ boson and the lightest neutralino ($\tilde\chi^0_1$), while the heavier neutralino ($\tilde\chi^0_2$) decays into the Standard Model 125 GeV Higgs boson and a second $\tilde\chi^0_1$ are presented. The signal selection requires a pair of $b$-tagged jets consistent with those from a Higgs boson decay, and either an electron or a muon from the $W$ boson decay, together with missing transverse momentum from the corresponding neutrino and the stable neutralinos. The analysis is based on data corresponding to 139 $\mathrm{fb}^{-1}$ of $\sqrt{s}=13$ TeV $pp$ collisions provided by the Large Hadron Collider and recorded by the ATLAS detector. No statistically significant evidence of an excess of events above the Standard Model expectation is found. Limits are set on the direct production of the electroweakinos in simplified models, assuming pure wino cross-sections. Masses of $\tilde{\chi}^{\pm}_{1}/\tilde{\chi}^{0}_{2}$ up to 740 GeV are excluded at 95% confidence level for a massless $\tilde{\chi}^{0}_{1}$.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Search for dark matter in events with a hadronically decaying vector boson and missing transverse momentum in p p collisions at s = 13 TeV with the ATLAS detector
CERN-LHC. This entry relates to the search for Dark Matter (DM) in association with a hadronically decaying vector boson with 36.1 fb-1 of pp collision data at a center-of-mass energy of sqrt(s) = 13 TeV recorded by the ATLAS detector at the LHC. In adition to hadronic decays of W and Z bosons, decays of the non-Standard-Model vector boson Z' of unknown masses are also considered for the first time (mono-Z'). The results are interpreted in terms of limits on the invisible Higgs boson decays into Dark Matter particles, constraints on the patamter space of the simplified vector-mediator model and generic upper limits on the visible detector-level cross sections for the W/Z+DM production. The results of the mono-Z' are shown in the frame of two simplified-model scenarios involving the DM production in assocaiation with the Z' boson. These are the dark Higgs model and the dark fermion model, each with a light and heavy dark sector scenario.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Cosmological attractor inflation from the RG-improved Higgs sector of finite gauge theory
The possibility to construct an inflationary scenario for renormalization-group improved potentials corresponding to the Higgs sector of finite gauge models is investigated. Taking into account quantum corrections to the renormalization-group potential which sums all leading logs of perturbation theory is essential for a successful realization of the inflationary scenario, with very reasonable parameter values. The inflationary models thus obtained are seen to be in good agreement with the most recent and accurate observational data. More specifically, the values of the relevant inflationary parameters, n{sub s} and r, are close to the corresponding ones in the R{sup 2} and Higgs-driven inflation scenarios. It is shown that the model here constructed and Higgs-driven inflation belong to the same class of cosmological attractors.
79 ASTRONOMY AND ASTROPHYSICS↗
Explaining the Higgs decays at the LHC with an extended electroweak model
We show that the observed enhancement in the diphoton decays of the recently discovered new boson at the LHC, which we assume to be a Higgs boson, can be naturally explained by a new doublet of charged vector bosons from extended electroweak models with SU(3)( )C( )ⓍSU(3)( )L( )ⓍU(1)( ) X symmetry. These models are also rather economical in explaining the measured signal strengths, within the current experimental errors, demanding fewer assumptions and less parameters tuning. Our results show a good agreement between the theoretical expected sensitivity to a 126–125 GeV Higgs boson, and the experimental significance observed in the diphoton channel at the 8 TeV LHC. Effects of an invisible decay channel for the Higgs boson are also taken into account, in order to anticipate a possible confirmation of deficits in the branching ratios into ZZ (*), WW (*), bottom quarks, and tau leptons.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Decays of Higgs Bosons Into a Fermion-Antifermion Pair
Within the framework of the Minimal Supersymmetric Standard Model, decay channels of Higgs bosons (h, A), H{sup ±} into arbitrarily polarized fermion-antifermion pairs H(h,A)→ (ff)-bar ,H{sup +}→ (ff)-bar {sup ′} have been investigated. Analytical expressions for the probabilities of the corresponding decays are obtained and their dependence on the mass of the Higgs bosons is investigated.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Planck 2013 results. XXV. Searches for cosmic strings and other topological defects
Planck data have been used to provide stringent new constraints on cosmic strings and other defects. We describe forecasts of the CMB power spectrum induced by cosmic strings, calculating these from network models and simulations using line-of-sight Boltzmann solvers. We have studied Nambu-Goto cosmic strings, as well as field theory strings for which radiative effects are important, thus spanning the range of theoretical uncertainty in the underlying strings models. We have added the angular power spectrum from strings to that for a simple adiabatic model, with the extra fraction defined as f 10 at multipole = 10. This parameter has been added to the standard six parameter fit using COSMOMC with flat priors. For the Nambu-Goto string model, we have obtained a constraint on the string tension of G μ/c 2 < 1.5 × 10 -7 and f 10 < 0.015 at 95% confidence that can be improved to G μ/c 2 < 1.3 × 10-7 and f 10 < 0.010 on inclusion of high-ℓ CMB data. For the Abelian-Higgs field theory model we find, G μ AH /c 2 < 3.2 × 10 -7 and f 10 < 0.028. The marginalised likelihoods for f 10 and in the f 10 -Ω b h 2 plane are also presented. We have additionally obtained comparable constraints on f 10 for models with semilocal strings and global textures. In terms of the effective defect energy scale these are somewhat weaker at G μ/c 2 < 1.1 × 10 -6 . We have made complementarity searches for the specific non-Gaussian signatures of cosmic strings, calibrating with all-sky Planck resolution CMB maps generated from networks of post-recombination strings. We have validated our non-Gaussian searches using these simulated maps in a Planck -realistic context, estimating sensitivities of up to Δ G μ/c 2 ≈ 4 × 10 -7 . We have obtained upper limits on the string tension at 95% confidence of G μ/c 2 < 9.0 × 10 -7 with modal bispectrum estimation and G μ/c 2 < 7.8 × 10 -7 for real space searches with Minkowski functionals. These are conservative upper bounds because only post-recombination string contributions have been included in the non-Gaussian analysis.
79 ASTRONOMY AND ASTROPHYSICS↗
Sleptonic SUSY: from UV framework to IR phenomenology
We study an attractive scenario, “Sleptonic SUSY”, which reconciles the 125 GeV Higgs scalar and the non-observation of superpartners thus far with potentially pivotal roles for slepton phenomenology: providing viable ongoing targets for LHC discovery, incorporating a co-annihilation partner for detectable thermal relic dark matter, and capable of mediating the potential muon g – 2 anomaly. This is accomplished by a modestly hierarchical spectrum, with sub-TeV sleptons and electroweakinos and with multi-TeV masses for the other new states. We study new elements in the UV MSSM realization of Sleptonic SUSY based on higher-dimensional sequestering and the synergy between the resulting gaugino-mediation, hypercharge D-term mediation and Higgs-mediation of SUSY-breaking, so as to more fully capture the range of possibilities. This framework stands out by harmoniously solving the flavor, CP and μ – Bμ problems of the supersymmetric paradigm. We discuss its extension to orbifold GUTs, including gauge-coupling and b-tau unification. We also develop a non-minimal model with extra Higgs fields, in which the electroweak vacuum is more readily cosmologically stable against decay to a charge-breaking vacuum, allowing a broader range of sleptonic spectra than in the MSSM alone. We survey the rich set of signals possible at the LHC and future colliders, covering both R-parity conservation and violation, as well as for dark matter detection. While the multi-TeV squarks imply a Little Hierarchy Problem, intriguingly, small changes in parameter space to improve naturalness result in dramatic phase transitions to either electroweak-preservation or charge-breaking. In a Multiverse setting, the modest unnaturalness may then be explained by the “principle of living dangerously”.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Higgs boson mass and sparticle spectroscopy in Yukawa unified SUSY SO(10)
We employ third family Yukawa unification, predicted by simple supersymmetric SO(10) models, to estimate the lightest MSSM Higgs boson mass. For {mu} > 0 (or {mu} < 0) and m{sub t} = 173.1GeV, the Higgs mass is estimated to lie close to 123-124 GeV. The theoretical uncertainty in this estimate is {+-}3 GeV. We highlight some LHC testable benchmark points which also display the presence of neutralino-stau coannihilation channel.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Search for light bosons in decays of the 125 GeV Higgs boson in proton-proton collisions at $ \sqrt{s}=8 $ TeV
A search is presented for decays beyond the standard model of the 125 GeV Higgs bosons to a pair of light bosons, based on models with extended scalar sectors. Light boson masses between 5 and 62.5 GeV are probed in final states containing four τ leptons, two muons and two b quarks, or two muons and two τ leptons. The results are from data in proton-proton collisions corresponding to an integrated luminosity of 19.7 fb$^{−1}$, accumulated by the CMS experiment at the LHC at a center-of-mass energy of 8 TeV. No evidence for such exotic decays is found in the data. Upper limits are set on the product of the cross section and branching fraction for several signal processes. The results are also compared to predictions of two-Higgs-doublet models, including those with an additional scalar singlet.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Lattice gauge theory for physics beyond the Standard Model
Our document is one of a series of white papers from the USQCD Collaboration. In it, we discuss opportunities for lattice field theory research to make an impact on models of new physics beyond the Standard Model, including composite Higgs, composite dark matter, and supersymmetric theories.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Nonuniversal gaugino masses and seminatural supersymmetry in view of the Higgs boson discovery
I consider models with non-universal gaugino masses at the gauge coupling unification scale, taking into account the Higgs boson discovery. Viable regions of parameter space are mapped and studied in the case of non-universality following from an F-term in a linear combination of singlet and adjoint representations of SU(5). I consider, in particular, "semi-natural" models that have small \mu, with gaugino masses dominating the supersymmetry breaking terms at high energies. Higgsino-like particles are then much lighter than all other superpartners, and the prospects for discovery at the Large Hadron Collider can be extremely challenging.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Natural SM-like 126 GeV Higgs boson via nondecoupling D terms
Accommodating both a 126 GeV mass and standard model (SM)-like couplings for the Higgs has a fine-tuning price in supersymmetric models. Examples are the minimal supersymmetric standard model, in which SM-like couplings are natural, but raising the Higgs mass to 126 GeV requires a considerable tuning, and the nonminimal supersymmetric standard model, in which the situation is reversed: the Higgs is naturally heavier, but being SM-like requires some tuning. We show that models with nondecoupling D terms alleviate this tension—a 126 GeV SM-like Higgs comes out basically with no fine-tuning cost. In addition, the analysis of the fine-tuning of the extended gauge sector shows that naturalness requires the heavy gauge bosons to likely be within the reach of LHC run II.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Singleton portals to the twin sector
The mirror twin Higgs framework allows for a natural Higgs mass while being consistent with collider bounds on colored symmetry partners to standard model quarks. This mechanism relies crucially on a discrete symmetry which relates each standard model field to a mirror partner. These partners are charged under gauge groups identical to, but distinct from, those in the standard model. The minimal twin Higgs scenario provides only one low-energy connection between the visible and twin sectors, the light Higgs boson. We present a new class of portals connecting the two sectors, using fields that have no twin partner under the discrete symmetry. Scalar, fermion, and vector states may provide such singleton portals, each with unique features and experimental signatures. The vector portal, in particular, provides a variety of renormalizable interactions relevant for the LHC. We provide concrete constructions of these portals and determine their phenomenology and opportunities to probe the twin sector at the LHC. We also sketch a scenario in which the structure of the twin sector itself can be tested.
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗