arXiv subjects

Brahim Ait Ouazghour

Publications and source records attributed to Brahim Ait Ouazghour.

4 recordsLinked to original sources

arXiv2025

Searching for charged Higgs bosons via $e^+ e^- \to H^\pm W^\mp S$ at the ILC

We investigate the phenomenology of the charged Higgs boson at the International Linear Collider (ILC) within the framework of the type-X Two-Higgs Doublet Model (2HDM), where a light charged Higgs boson, with a mass around 200 GeV or even smaller than top quark mass, is still being consistent with flavor physics data as well as with the colliders experimental data. In the theoretically and experimentally allowed parameter space, the $e^+ e^- \to H^\pm W^\mp S$ (with $S = H, A$) production processes can yield signatures with event rates larger than those from $e^+ e^- \to H^+ H^-$ and offer sensitivity to the Higgs mixing parameter $\sin(β-α)$. We consider the bosonic $H^\pm \to W^\pm S$ decays, where the neutral scalar $S$ further decays into a pair of tau leptons. We show, through a detector-level Monte Carlo analysis, that the resulting $[ττ][ττ] WW$ final state could be seen at the ILC with at least 500 GeV center-of-mass energy and 500 fb$^{-1}$ of luminosity.

hep-ph↗

arXiv2024

Associated charged Higgs production within the 2HDM: $e^-e^+$ versus $μ^-μ^+$ colliders

Our goal is to investigate the charged Higgs phenomenology in the framework of 2HDM at the upcoming $e^+e^-$ and muon colliders. We are primarily concerned with the associated production processes with a fermion pair: $\ell^+ \ell^- \to τ^+ ν_{τ}H^-$ and $\ell^+ \ell^- \to t \bar{b} H^-$, as well as with the W boson and a neutral Higgs boson: $\ell^+ \ell^- \to W^\pm H^\mp S$ ($S=h,\,H,\, A$) and $\ell^+ \ell^- \to W^\pm H^\mp Z$. We first update the results for $e^+e^- \to \{ τ^+ ν_{τ}H^-\ , \ t \bar{b} H^-\}$ and then discuss our findings for $e^+e^- \to \{ W^\pm H^\mp S\}$ for various center of mass energies 500 GeV, 1 TeV, 1.5 TeV and 3 TeV. In the case of muon collider, we show that the new s-channel and t-channel diagrams can increase the cross sections by virtue of their Yukawa couplings. We systematically compare our results for the muon collider with those obtained at the International Linear (ILC) and Compact Linear (CLIC) colliders. We select benchmark points and conduct signal-background analyses, incorporating detector simulations. For a 3 TeV muon collider, our results show an exclusion region at the 2$σ$ level and a discovery region at the 5$σ$ level.

hep-ph↗

arXiv2024

Comparison between $μ^{-}μ^{+}$ and $e^{-}e^{+}$ colliders for charged Higgs production in 2HDM

We study the phenomenology of the charged Higgs boson at future muon colliders. We investigate both the pair production $μ^+ μ^- \to H^+ H^-$, the single production $μ^+ μ^- \to W^\pm H^\mp$, as well as the Vector Boson Fusion (VBF) $\{e^+e^-, μ^+ μ^-\} \to ν\barν H^+ H^-$. We show that the neutral Higgs exchange diagrams in the muon collider case can lead to a significant boost in the cross sections through their Yukawa couplings. Our results for the muon collider are systematically compared to the corresponding ones at $e^+e^-$ machines. It is demonstrated that the vector boson fusion (VBF) $e^+e^- \to ν\barν H^+ H^-$ can compete with the mentioned $2\to 2$ processes. We select benchmark points and perform signal-background analyses, taking into account detector simulations. We demonstrate the discovery region at $5σ$ and the excluded region at $2σ$ levels at a 3 TeV muon collider.

hep-ph↗

arXiv2019

Theory and Phenomenology of Two Higgs Doublet Type-II Seesaw Model at the LHC Run-2

We study the most popular scalar extension of the Standard Model, namely the Two Higgs doublet model, extended by a complex triplet scalar (2HDMcT). Such considering model with a very small vacuum expectation value, provides a solution to the massive neutrinos through the so-called type II seesaw mechanism. We show that the 2HDMcT enlarged parameter space allow for a rich and interesting phenomenology compatible with current experimental constraints. In this paper the 2HDMcT is subject to a detailed scrutiny. Indeed, a complete set of tree level unitarity constraints on the coupling parameters of the potential is determined, and the exact tree-level boundedness from below constraints on these couplings are generated for all directions. We then perform an extensive parameter scan in the 2HDMcT parameter space, delimited by the above derived theoretical constraints as well as by experimental limits. We find that an important triplet admixtures are still compatible with the Higgs data and investigate which observables will allow to restrict the triplet nature most effectively in the next runs of the LHC. Finally, we emphasize new production and decay channels and their phenomenological relevance and treatment at the LHC.

hep-ph↗