We discuss the process of Higgs boson production in $γγ$ collider on noncommutative spacetime and compare the results with large extra dimension in KK graviton channel. Summing all KK mode on IR brane, the affections are in the same order by comparing noncommutatve model prediction. This process is completely forbidden in standard model on unitarity condition and bosonic distribution. In noncommutative theory, the effect is induced by the coordinates noncommutable relation, $[x^μ, x^ν]$ = $iθ^{μν}$. Due to the constant background strength tensor does not contain any conserved quantum number, hence, this effort is indicated into particle power spectrum. Particle mass spectrum is corrected by radiational and anisotropic surroundings. The process of $γγ\to H^{0}H^{0}$ restricts the unitarity condition in noncommutative field theory. Under power law conservation condition, the neutral Higgs mass below gauge boson resonance will produce a accelerated phenomena as the central energy is higher than $Z_{0}$ gauge boson creation scale. The effects generated from the vast light Higgs particles descend the power rate energy distribution as far as the ambient is under a balance. The fractional rate on polarized polars are very small embedded into the unpolarized surroundings depend on background electric field couplings.
In this work, we analyse and demonstrate possible strategies to explore extended Higgs sector of the Minimal Supersymmetric Standard Model (MSSM). In particular we concentrate on heavy Higgs decays to electroweakinos. We analyse the Higgs to electroweakino decays in the allowed MSSM parameter space after taking into account 13 TeV LHC searches for supersymmetric particles and phenomenological constraints such as flavour physics, Higgs measurements and dark matter constraints. We explore some novel aspects of these Higgs decays. The final states resulting from Higgs to electroweakino decays wil…
We studied the interplay between the mass reach for electroweakinos at future hadron colliders and direct detection experiments. The lack of new phenomena at the LCH motivates us to focus on split supersymmetry scenarios with different electroweakino spectra. A 100 TeV hadron collider may reach masses up to 3 TeV in models of anomaly mediation with long-lived thermal Winos. Moreover, in scenarios where the lightest neutralino is not the only dark matter component, the interplay between collider searches and direct detection experiments might cover large part of the parameter space.
We examine the electroweak gauge sector of noncommutative standard model and in particular, obtain the $\mathcal{O} \,(θ)$ Feynman rules for all quadrilinear gauge boson couplings. Surprisingly, an electroweak-chromodynamics mixing appears in the gauge sector of noncommutative standard model, where photon as well as the neutral weak boson are coupled directly to three gluons. The phenomenological perspectives of the model in $W^-W^+ \rightarrow Z Z$ scattering are studied and it is shown that there is a characteristic oscillatory behaviour in azimuthal distribution of scattering cross sections…
The Standard Model Effective Field Theory (SMEFT) provides a powerful theoretical framework for searching for subtle deviations from the Standard Model. In this talk, we present the results from a global fit of the dimension-6 operators of the SMEFT to a combination of Higgs, top, diboson and electroweak precision observables. SMEFT constraints driven by data from the top quark sector are highlighted. We explore the interplay between the top and Higgs sectors, emphasising the need for a global approach to constraining the SMEFT.
The Georgi-Machacek (GM) model is one of many Beyond Standard Model scenarios with an extended scalar sector which can group under the custodial $\rm SU(2)_C$ symmetry into a fiveplet, a triplet, and two singlets. The heavy charged custodial fiveplet Higgs $\rm H_5^{\pm}$ are typical particles in GM model which couple to the electroweak gauge bosons, therefore provide a good testing ground for the detection of the $\rm H^\pm W^\mp Z$ vertex. The neutral custodial fiveplet Higgs $\rm H_5^{0}$ in the GM model has the same mass with $\rm H_5^{\pm}$ and couples to the electroweak gauge bosons $\rm…
We propose leveraging our proficiency for detecting Higgs resonances by using the Higgs as a tagging object for new heavy physics. In particular, we argue that searches for exotic Higgs production from decays of color-singlet fields with electroweak charges could beat current searches at the LHC which look for their decays to vectors. As an example, we study the production and decay of vector-like leptons which admit Yukawa couplings with SM leptons. We find that bounds from Run 2 searches are consistent with anywhere from hundreds to many thousands of Higgses having been produced in their dec…
{\it Why continue looking for supersymmetry?} Over and above the aesthetic and theoretical motivations from string theory, there are several longstanding phenomenological motivations for TeV-scale supersymmetry such as the electroweak scale, and the lightest supersymmetric particle (LSP) as cold dark matter. Run~1 of the LHC has actually provided three extra motivations, namely the stabilization of the electroweak vacuum, and successful predictions for the Higgs mass and couplings. {\it How to look for it?} There are several examples of emergent supersymmetry, the most recent being on the surf…
Noncommutative (NC) space-time leads to some strong constraints on the possible choices of gauge groups and allowed representations of matter and gauge fields. The standard model based on $U(3)\times U(2)\times U(1)$ can be transcribed to NC space-time consistently with these constraints \cite{nNCSM}. In fact, through two new symmetry reduction mechanisms, this gauge group is reduced to the usual standard model one. In this paper, we show that, on the contrary to the usual standard model, the Goldestone boson equivalence theorem is violated due to the incompatibility of the new symmetry reduct…
Electroweak-interacting massive particles (EWIMPs) exist in a broad class of new physics models beyond the Standard Model. Searching for such particles is one of most primary goal at the LHC and future colliders. The EWIMP generally affects the LHC signatures through quantum corrections even without direct productions. By measuring the Standard Model processes precisely, we can indirectly probe the EWIMPs. In this paper, we study the current constraint and future prospect of the EWIMPs by using the precision measurements of mono-lepton production from the charged Drell-Yan processes at hadron …
In this paper, using a Bestest Little Higgs Model (BLHM) approach, we obtain bounds on the top-quark electromagnetic and weak dipole moments. These physical observables are sensitive to quantum corrections induced by virtual particles at the one-loop level. The contributions of the virtual particles are obtained from the vertices of scalar bosons, vector bosons, and heavy quarks: $tq_iS_i$, $S_i=h_0, H_0, A_0, ϕ^{0}, η^{0}, σ, H^{\pm}, ϕ^{\pm}, η^{\pm}$; $tq_iV_i$, $V_i= γ, Z, W, Z', W'$; $V q_i\bar q_i$, $V=γ,Z$, $q_i=b, t, B, T, T_5, T_6, T^{2/3}, T^{5/3}$; $ V W^{-}_{i}Φ^{+}_i $, $W_{i} \eq…
Chasing the two-Higgs-doublet model via electroweak corrections at $e^+e^-$ colliders
University of Siegen（锡根大学）；Nagoya University（名古屋大学）；Karlsruhe Institute of Technology（卡尔斯鲁厄理工学院）；Université catholique de Louvain（天主教鲁汶大学）；Deutsches Elektronen-Synchrotron DESY（德国电子同步加速器研究所）；CERN（欧洲核子研究中心）
We investigate a mono-Z process as a potential dark matter search strategy at the LHC. In this channel a single Z boson recoils against missing transverse momentum, attributed to dark matter particles, $χ$, which escape the detector. This search strategy is related, and complementary to, monojet and monophoton searches. For illustrative purposes we consider the process $q\bar{q} -> χχZ$ in a toy dark matter model, where the Z boson is emitted from either the initial state quarks, or from the internal propagator. Among the signatures of this process will be a pair of muons with high pT that rec…
Vector boson fusion (VBF) processes offer a promising avenue to study the non-colored sectors of supersymmetric extensions of the Standard Model at the LHC. A feasibility study for searching for the chargino/neutralino system in the $R-$parity conserving Minimal Supersymmetric Standard Model is presented. The high $E_T$ forward jets in opposite hemispheres are utilized to trigger VBF events, so that the production of the lightest chargino and the second lightest neutralino can be probed without a bias by experimental triggers. Kinematic requirements are developed to search for signals of these…
We analyse in a model independent way the possibilities of digging out neutral exotic Higgs states, should they exist endowed with unconventional couplings with ordinary matter and gauge fields, at the 14 TeV run of the Large Hadron Collider (LHC), adding some comparative studies for 13.6 and 13 TeV runs. Flavor models, based on some discrete symmetry groups, with extended scalar sectors are known to yield exotic spin-0 states, both CP-even and CP-odd, with purely flavor off-diagonal Yukawa couplings. The gauge interaction of one such CP-even state is also unusual that, unlike the Standard Mod…
We study the search for electroweakinos at the 13 TeV LHC in the case of heavy scalar superpartners. We consider both the direct production mode and the one associated with the decay of heavy Higgs bosons, and concentrate on the case of light Higgsinos and Binos. In this case, the direct production searches becomes more challenging than in the light Wino scenario. In the direct production mode, we use the current experimental searches to set the reach for these particles at larger luminosities, and we emphasize the relevance of considering both the neutral gauge boson and the neutral Higgs dec…
The $W$ boson mass is one of the most important electroweak precision observables for testing the Standard Model or its extensions. The very recent measured $W$ boson mass at CDF shows about $7σ$ deviations from the SM prediction, which may challenge the internal consistency of the SM. By performing the global electroweak fit with the new $W$-boson, we present the new values of the oblique parameters: $S = 0.06 \pm 0.10$, $T= 0.11 \pm 0.12$, $U=0.13 \pm 0.09$, or $S=0.14 \pm 0.08$, $T= 0.26 \pm 0.06$ with $U =0$ and the corresponding correlation matrices, which strongly indicates the need for …
The structure of the Higgs sector is a major issue in the quest of a detailed description of the electroweak interactions. Most of the effort is devoted to the study of the standard model--like Higgs boson at 126 GeV, however the experimental collaborations at the LHC are also searching for extra scalar particles whose presence may hint to an extended Higgs sector, typical of many extensions of the standard model. We study a model independent parametrisation of a scalar particle lighter than the 126 GeV Higgs boson, which may be easily implemented in the ongoing searches by ATLAS and CMS. Inde…
Strongly coupled models at the TeV scale often predict one or more neutral spin-one resonances (Z') which have appreciable branching fractions to electroweak bosons, namely the Higgs and longitudinal W and Z. These resonances are usually believed to have multi-TeV mass due to electroweak precision constraints, placing them on the edge of LHC discovery reach. Searching for them is made particularly challenging because hadronically decaying electroweak bosons produced at such high energy will appear very similar to QCD jets. In this work we revisit the possibility of discovering these resonances…
We describe the Resummino package, a C++ and Fortran program dedicated to precision calculations in the framework of gaugino and slepton pair production at hadron colliders. This code allows to calculate transverse-momentum and invariant-mass distributions as well as total cross sections by combining the next-to-leading order predictions obtained by means of perturbative QCD with the resummation of the large logarithmic contributions arising in the small transverse-momentum region and close to the production threshold. The results computed in this way benefit from reduced theoretical uncertain…
The electroweak sector of the Minimal Supersymmetric Standard Model (MSSM) - neutralinos, charginos and sleptons - remains relatively weakly constrained at the LHC due in part to the small production cross sections of these particles. In this paper, we study the prospects of searching for decays of heavy Higgs bosons into these superpartners at the high luminosity LHC. In addition to the kinematic handles offered by the presence of a resonant particle in the production chain, heavy Higgs decays can be the dominant production modes of these superpartners, making it possible to extend coverage t…
We study a search for the charged Higgs boson via $e^+e^- \to H^+H^- \to c\bar{b}\bar{c}b$ at the 500 GeV ILC. In a general two Higgs doublet model without $Z_2$ symmetry, extra Yukawa couplings $ρ_{tt}$ and $ρ_{tc}$ can drive baryogenesis, but searches at the HL-LHC may still go empty-handed if the couplings are relatively weak. Taking $m_{H^+ } \simeq m_H \simeq m_A \simeq 200$ GeV, with $ρ_{tt}$, $ρ_{tc}\sim 0.1$ and no $h(125)$-$H$ mixing, $H^+ \to c\bar b$ decay is dominant, and the $c\bar{b}\bar{c}b$ final state is likely overwhelmed by QCD background at the LHC. We show that the electro…
As the planning stages for a high energy muon collider enter a more concrete era, an important question arises as to what new physics could be uncovered. A TeV-scale muon collider is also a vector boson fusion (VBF) factory with a very clean background, and as such it is a promising environment to look for new physics that couples to the electroweak (EW) sector. In this paper, we explore the ability of a future TeV-scale muon collider to search for Majorana and Dirac Heavy Neutral Leptons (HNLs) produced via EW bosons. Employing a model-independent, conservative approach, we present an estimat…
The search for evidence of extended electroweak symmetry breaking has entered a new phase with the discovery of a Standard Model (SM)-like Higgs at the LHC. The measurement of Higgs couplings and direct searches for additional scalars provide complementary avenues for the discovery of new degrees of freedom. This complementarity is particularly sharp in two Higgs doublet models (2HDMs) where the couplings of the SM-like Higgs may be directly related to the LHC signals of additional scalars. In this work we develop a strategy for searching for the second Higgs doublet given the LHC signals of t…
We study LHC Higgs signatures from the extended electroweak gauge symmetry SU(2) x SU(2) x U(1). Under this gauge structure, we present an effective UV completion of the 3-site moose model with ideal fermion delocalization, which contains two neutral Higgs states (h, H) and three new gauge bosons (W', Z'). We study the unitarity, and reveal that the exact E^2 cancellation in the longitudinal WW scattering amplitudes is achieved by the joint role of exchanging both spin-1 new gauge bosons and spin-0 Higgs bosons. We identify the lighter Higgs state h with mass 125GeV, and derive the unitarity b…
The existence of the tiny neutrino mass and the flavor mixing can be naturally explained by type-I Seesaw model which is probably the simplest extension of the Standard Model (SM) using Majorana type SM gauge singlet heavy Right Handed Neutrinos (RHNs). If the RHNs are around the Electroweak(EW)-scale having sizable mixings with the SM light neutrinos, they can be produced at the high energy colliders such as Large Hadron Collider (LHC) and future $100$ TeV proton-proton (pp) collider through the characteristic signatures with same sign di-lepton introducing lepton number violations(LNV). On t…
The discovery of a Higgs boson at the LHC begins the era of directly measuring the mechanism of electroweak symmetry breaking (EWSB). Searching for extensions of the Standard Model (SM) EWSB sector at the LHC is of vital importance. An important extension of the SM with an extended EWSB sector is the Minimal Supersymmetric Standard Model (MSSM). In this white paper, we extend current ATLAS and CMS bounds on direct searches for the heavy MSSM neutral Higgs bosons to 300 fb^-1 and 3000 fb^-1 of data at the LHC. In particular we focus on the τ^+τ^- channel and the pseudoscalar decay to light Higg…
We study the nature of the electroweak phase transition (EWPT) in models where the Higgs emerges as a pseudo-Nambu-Goldstone boson of an approximate global symmetry of a new strongly-interacting sector confining around the TeV scale. Our analysis focusses for the first time on the case where the EWPT is accompanied by the confinement phase transition of the strong sector. We describe the confinement in terms of the dilaton, the pseudo-Nambu-Goldstone boson of spontaneously broken conformal invariance of the strong sector. The dilaton can either be a meson-like or a glueball-like state and we d…
The recently announced Higgs discovery marks the dawn of the direct probing of the electroweak symmetry breaking sector. Sorting out the dynamics responsible for electroweak symmetry breaking now requires probing the Higgs interactions and searching for additional states connected to this sector. In this work we analyze the constraints on Higgs couplings to the standard model gauge bosons using the available data from Tevatron and LHC. We work in a model--independent framework expressing the departure of the Higgs couplings to gauge bosons by dimension--six operators. This allows for independe…
Since no direct signs of new physics have been observed so far indirect searches in the Higgs sector have become increasingly important. With the discovered Higgs boson behaving very Standard Model (SM)-like, however, indirect new physics manifestations are in general expected to be small. On the theory side, this makes precision predictions for the Higgs parameters and observables indispensable. In this paper, we provide in the framework of the CP-violating Next-to-Minimal Supersymmetric extension of the SM (NMSSM) the complete next-to-leading order (SUSY-)electroweak corrections to the neutr…
Searching for a Charged Higgs Boson in Top-Quark Decays via the $WZ$ Mode
Karlsruhe Institute of Technology（卡尔斯鲁厄理工学院）；Universitat Autònoma de Barcelona（巴塞罗那自治大学）；ICREA, Institució Catalana de Recerca i Estudis Avançats（加泰罗尼亚高级研究学院）；University of the Witwatersrand（威特沃特斯兰德大学）；iThemba LABS, National Research Foundation（国家研究基金会iThemba实验室）；Indian Institute of Science Education and Research Pune（印度科学教育研究所浦那校区）
High-energy colliders offer a unique sensitivity to dark photons, the mediators of a broken dark U(1) gauge theory that kinetically mixes with the Standard Model (SM) hypercharge. Dark photons can be detected in the exotic decay of the 125 GeV Higgs boson, h -> Z Z_D -> 4l, and in Drell-Yan events, pp -> Z_D -> ll. If the dark U(1) is broken by a hidden-sector Higgs mechanism, then mixing between the dark and SM Higgs bosons also allows the exotic decay h -> Z_D Z_D -> 4l. We show that the 14 TeV LHC and a 100 TeV proton-proton collider provide powerful probes of both exotic Higgs decay channe…
