The large top quark samples collected with the ATLAS experiment at the LHC have yielded measurements of the production cross section of unprecedented precision and in new kinematic regimes. They have also enabled new measurements of top quark properties that were previously inaccessible, enabled the observation of many rare top quark production processes predicted by the Standard Model and...
This talk covers recent measurements on top-pair production, and top-pair in association with additional boson or quarks, using the data collected by the CMS detector. Differential measurements of tt+X processes under the EFT framework are also presented.
The top-quark pair production in association with a W boson is an important background to processes like t¯tH or 4-top production. Due to higher order electroweak corrections, the process is difficult to model. In consequence, a difference between the measured and the predicted value for σ(t¯tW) has been observed in previous analyses. To improve our understanding of this process, a new...
Higgs pair production is a one-loop process, which is potentially sensitive to BSM physics, which can also enter at one loop. We look at the case of light stops in the MSSM and NMSSM. We developed a method, where factorise the cross section to a part depending only on the couplings and a part with all mass dependences and we can efficiently produce kinematical distributions for varying...
In this talk, within the bottom-up approach to holography, I will consider a class of six-dimensional gravity models and solutions that can be interpreted in terms of dual five-dimensional conformal field theories deformed by a single scalar operator. The scaling dimension of this operator is treated as a free parameter. One dimension in the geometry is compactified on a shrinking circle,...
A vector boson $W_{1}$ with the quantum numbers $\left(3,1\right)$ under the electroweak group $SU\left(2\right)_{L}\times U(1)_{Y}$ could in principle couple
with the Higgs field via the renormalizable term $W_{1}^{\mu*}H D_{\mu}H$. This interaction is known to affect the $T$ parameter and, in so doing, it could potentially explain the 2022 CDF measurement of the W-boson mass.
As it is...
In this talk, I delve into the potential of multi-scalar interactions within the $\kappa$-framework as effective discriminators of BSM physics at current and upcoming colliders. By analysing the existing and projected collider constraints on these coupling modifiers, we can identify deviations from the Standard Model expectations, which serve as signposts for BSM discoveries. Building upon...
Using the $\kappa$ framework, the constraints on the quartic interactions of Higgs with gauge bosons give a qualitative picture of consistency with the SM when the statistical yield is low. However, increasing statistics demand a more theoretically consistent framework to limit such couplings. Adopting the Higgs Effective Field Theory (HEFT) framework, we calculate the radiative corrections to...
This talk reviews recent measurements of multiboson production using CMS data. Inclusive and differential cross sections are measured using several kinematic observables.
CP-violating contributions to Higgs--fermion couplings are absent in the standard model of particle physics (SM) but are motivated by models of electroweak baryogenesis. In this talk, I will present results of a study of the constraints on these couplings from a combination of LHC data and experimental bounds on the electron, neutron, and mercury electric dipole moments (EDMs). While previous...
At the proposed future Large Hadron-Electron Collider (LHeC), the coupling between the Higgs boson (H) and the massive gauge bosons (V = W, Z) of weak interaction can be investigated through the single Higgs boson production. In this presentation, I will focus on the potential of the collider to determine constraints on the new physics parameters associated with the most general structure...
The event rates and kinematics of Higgs boson production and decay processes at the LHC are sensitive probes of possible new phenomena beyond the Standard Model (BSM). This talk presents precise measurements of Higgs boson production and decay rates, obtained using the full Run 2 and partial Run 3 pp collision dataset collected by the ATLAS experiment at 13 TeV and 13.6 TeV. These include...
This talk presents precise measurement of the properties of the Higgs boson, including its mass, total width, spin, and CP quantum number. The measurements are performed in various Higgs boson production and decay modes, as well as their combinations. Observation of deviations between these measurements and Standard Model (SM) predictions would be a sign of possible new phenomena beyond the SM
In this talk we discuss recent results from the CMS experiment on Higgs boson coupling and cross section measurements. A variety of different production modes and final states are discussed. We also present differential cross section measurements and constraints on anomalous Higgs boson couplings.
We introduce a methodology and investigate the feasibility of measuring quantum properties of tau lepton pairs in the $𝐻 \to \tau^+ \tau^−$ decay at future lepton colliders. In particular, observation of entanglement and violation of Bell inequalities are examined for the ILC and FCC-ee. As a by-product, we show that a novel model-independent test of CP violation can be performed and the...
More than twenty years ago a paradigm emerged according to which supersymmetric theories with compact extra dimensions and Scherk-Schwarz SUSY breaking could naturally provide a UV-insensitive Higgs mass $m_H$, and more generally a UV-insensitive Higgs potential $V_{1l}(\phi)$. Some warnings were originally raised on the validity of such an outcome, but the community soon came to an agreement...
Searches are being carried out at the Large Hadron Collider (LHC) for the decay of the CP-odd scalar $(A^{0})$ in Two-Higgs-Doublet Models (2HDMs) with Natural Flavour Conservation (NFC) in the channel $A^{0}\rightarrow h^{0}Z^{*}$ (with $m_{h^{0}}=125 GeV$ and Z on-shell). In the absence of any signal, limits on the parameter space of $[tan\beta , cos(\beta -\alpha ), m_{A^{0}}]$in each 2HDM...
The discovery of the Higgs boson with the mass of about 125 GeV completed the particle content predicted by the Standard Model. Even though this model is well established and consistent with many measurements, it is not capable to solely explain some observations. Many extensions of the Standard Model addressing such shortcomings, including several SUSY benchmark models, introduce additional...
We present searches for additional Higgs bosons with data collected by the CMS experiment. Searches for additional Higgs bosons at high mass, such as those that can constrain the parameter space of the minimal supersymmetric standard model, will be discussed. We also cover searches for the 125 GeV Higgs boson decaying to a pair of light scalars.
The ATLAS collaboration has recently reported the results of a low-mass Higgs-boson search in the di-photon final state based on the full Run 2 data set. The largest "excess" is observed at 95.4 GeV with a significance of 1.7 $\sigma$. At exactly the same mass in the same channel CMS reported earlier an excess of 2.9 $\sigma$. Other excesses at about the same mass have been published by LEP in...
In the Standard Model, the ground state of the Higgs field is not found at zero but instead corresponds to one of the degenerate solutions minimising the Higgs potential. In turn, this spontaneous electroweak symmetry breaking provides a mechanism for the mass generation of nearly all fundamental particles. While the Standard Model makes a definite prediction for the Higgs boson self-coupling...
In supersymmetric theories the Higgs boson masses are derived quantities where higher-order corrections have to be included in order to match the measured Higgs mass value at the precision of current experiments. Closely related through the Higgs potential are the Higgs self-interactions. In addition, the measurement of the trilinear Higgs self-coupling provides the first step towards the...
Vector boson scattering is a key production process to probe the electroweak symmetry breaking of the standard model, since it involves both self-couplings of vector bosons and coupling with the Higgs boson. If the Higgs mechanism is not the sole source of electroweak symmetry breaking, the scattering amplitude deviates from the standard model prediction at high scattering energy. Moreover,...
Here, we investigate the parameter space of the Georgi-Machacek
(GM) model in both cases where the extra CP-even scalar could be lighter or heavier than the Higgs. W consider many theoretical and experimental constraints, in addition to the constraints from doubly charged
Higgs bosons and Drell-Yan di-photon production and the indirect constraint from the $b\to s$ transition processes. We...
Phenomenological implications of the simplest multi-Higgs extensions of the Standard Model constrained by additional global horizontal flavour symmetries will be overviewed. A particular focus would be given to their basic implications for Higgs and flavour physics as well as for possible detection of primordial gravitational waves.
MicroBooNE is an 85-tonne active mass liquid argon time projection chamber (LArTPC) at Fermilab. With an excellent calorimetric, spatial and energy resolution, the detector was exposed to two neutrino beams between 2015 and 2020. These characteristics make MicroBooNE a powerful detector not just to explore neutrino physics, but also for Beyond the Standard Model (BSM) physics. Recently,...
Observation of Multiple Parton Scattering at High Energy Proton-Proton Collisions
M. Y. Hussein
Search Center
Shaikh Ebrahim Bin Mohammed Al-Khalifa Center for Culture and Research
Muharraq, P.O Box 13725
Kingdom of Bahrain
Multiple parton scattering “MPS” occurs when two or more independent identified hard particle from each proton takes place in the same proton-proton...
We discuss triple Higgs couplings (THCs) in the 2 Higgs Doublet Model (2HDM). We show how the SM-like THC, but also BSM THCs involving BSM Higgs bosons can be tested in di-Higgs production at the HL-LHC. We emphasize the role of experimental uncertainties in the measurement of these processes.
The detection of a heavy neutral CP-even Higgs boson of the $B-L$ Supersymmetric Standard Model (BLSSM), $h'$, with $m_{h'}\simeq 400~\text{GeV}$, at the Large Hadron Collider (LHC) for a center-of-mass energy of $\sqrt{s}=14~\text{TeV}$, is investigated. The following production and decay channels are considered: $gg\to h'\to{ZZ}\to4\ell$ and $gg\to h'\to{W^+W^-}\to2\ell+MET$ (with $MET$...
Recent results on inclusive W and Z boson productions obtained with the LHC Run 2 and run 3 proton collision data by the CMS collaboration are presented.
We present the latest results from the CMS experiment on searches for non-resonant di-Higgs production. In addition to an overview of the different channels that have been probed, we present constraints on the Higgs-boson self-coupling, the quartic coupling between two Higgs bosons and two vector bosons, as well as on anomalous interactions that affect the production of a pair of Higgs bosons....
