arXiv subjects

Mohamed Chabab

Publications and source records attributed to Mohamed Chabab.

At least 19 recordsLinked to original sources

arXiv2026

Can $\gamma\gamma$ collisions rival $e^-e^+$ in probing doubly charged Higgs bosons?

High-energy $\gamma\gamma$ collisions, realizable as an operational mode of future lepton linear colliders such as the ILC and CLIC, provide a promising environment to probe extended Higgs sectors. We investigate the sensitivity of such colliders to doubly charged Higgs bosons within the 2-Higgs Doublet Model with type-II seesaw (2HDMcT). Focusing on the three-body production channels $\gamma\gamma \to H^{\pm\pm}H_1^{\mp}H_1^{\mp}$ and $\gamma\gamma \to H^{\pm\pm}H_1^{\mp}W^{\mp}$, we perform a parameter space scan consistent with theoretical constraints as well as current collider, flavor, and electroweak precision observables (EWPOs). We show that $\gamma\gamma$ collisions can rival the discovery potential of the conventional $e^+e^-$ mode for probing doubly charged Higgs bosons through a $4\ell+E_T^{miss}$ signature ($\ell=e,\mu$). Despite the reduced effective luminosity resulting from the photon spectrum, the significantly enhanced production cross sections, exceeding those in electron-positron collisions by more than one order of magnitude, compensate for this limitation. By performing a detailed signal-to-background analysis at center-of-mass energies of $\sqrt{s}=830$ and $1245$ GeV, we demonstrate that a discovery significance at the $5\sigma$ level can be achieved for viable benchmark points (BPs).

hep-ph↗

arXiv2026

Thermodynamic stability and geometric thermodynamics of charged black holes in Rastall-massive gravity under quintessence

In the present paper, we derive a new charged black hole solution embedded in a quintessence field within a framework combining the Rastall and massive gravity in an asymptotically flat spacetime. We interpret the integration constant associated with the structural properties of the quintessence field as a thermodynamical variable. In this context, several limiting cases have been explored with the aim to shed light on the role of the model parameters. Then, we analyse the thermodynamic properties and stability of the charged black holes in flat spacetime, where the quintessence field is characterized by the state parameter $ \omega_q = -2/3 $. Detailed studies are perfomed to see how the various parameters affect phase transitions between small and large black holes. In particular, we establish a connection between the impact parameter and unstable circular photon orbits with the thermodynamic phase transitions. Our analysis suggest that the photon sphere observables could remarkably provide an indirect observational signature of black hole thermodynamic critical transitions. Generally, thanks to the effective contribution of the quintessence parameter, we found that the overall thermodynamic behavior basically resembles that of the charged RN--AdS black hole with thermal features analogous to of a Van der Waals fluid ones. Finally, we have checked these findings using thermodynamic geometry with the Quevedo metric. Our results showed that the critical behaviour derived from the standard thermodynamics is fully consistent with geothermodynamics description, where the phase structure and divergence points exactly coincide with those identified from heat capacity and Gibbs free energy analyses.

hep-th↗

arXiv2026

Probing Doubly Charged Higgs Bosons with Three-Body Associated Production at Future $e^+e^-$ Colliders

We study the discovery prospects for a doubly charged Higgs boson $H^{\pm\pm}$ in the 2-Higgs doublet model with type-II seesaw at future $e^+e^-$ colliders. Focusing on the three-body channels $e^+e^- \to H^{\pm\pm}H_1^{\mp}H_1^{\mp}$ and $e^+e^- \to H^{\pm\pm}H_1^{\mp}W^{\mp}$, we scan the model parameter space subject to theoretical consistency as well as current collider, flavor and electroWeak precision observables (EWPOs). We find that these $2\to3$ production modes can exceed the conventional pair-production rate $e^+e^- \to H^{++}H^{--}$, followed by $H^{\pm\pm}\to H_1^{\pm}H_1^{\pm}$ and $H^{\pm}_1W^{\pm}$ decays, over wide regions, particularly above the $H^{\pm\pm}\to H_1^{\pm}H_1^{\pm}$ and $H^{\pm\pm}\to H_1^{\pm}W^{\pm}$ thresholds, reaching cross sections up to ${\cal O}(10^2)$~fb for $\sqrt{s}=500$--$1500$~GeV. A detector-level analysis of the $4\ell + E_T^{\text{miss}}$ signature, including dominant multiboson and top quark backgrounds, shows that discovery sensitivity is achievable for $\sqrt{s}=1000$-$1500$~GeV with integrated luminosities in the few ab$^{-1}$ range, even in the presence of realistic systematic uncertainties.

hep-ph↗

arXiv2025

A comprehensive study of the charged Higgs boson in the two Higgs doublet type-II seesaw model

We investigate the phenomenology of the charged Higgs boson within the Two-Higgs-Doublet Type-II Seesaw Model (2HDMcT Type-III) at future $μ^+ μ^-$ colliders. Focusing on $2 \to 2$ processes such as $μ^+ μ^- \to H^+_1 S^-$ ($S^- = H^-_1, H^-_2$) and $μ^+ μ^- \to H^+_1 W^-$, we incorporate both theoretical and experimental constraints to assess their production prospects. We find that $σ(μ^+ μ^- \to H_1^+ H_1^-)$ can reach or exceed the corresponding $e^+ e^-$ cross section, while $σ(μ^+ μ^- \to H_1^+ H_2^-)$ is roughly eighteen times smaller but can be enhanced up to 0.62 fb upon relaxing electroweak precision observables constraints. Moreover, we observe that the cross section for $μ^+ μ^- \to H^+_1 W^-$ is significantly enhanced due to the large $\tanβ$ amplification characteristic of the Type-III scenario. Furthermore, we conduct a signal-background analysis and determine the discovery ($5σ$) regions at a 3 TeV muon collider for the $μ^+ μ^- \to H_1^+ H_1^-$, $μ^+ μ^- \to H_1^+ H_2^-$, and $μ^+ μ^- \to W^\pm H_1^\mp$ processes.

hep-ph↗

arXiv2025

Particle emission spectrum and thermodynamics phase transition of RN-AdS black hole in massive gravity via a new prescription

In this paper we investigate the shadow and energy emission rate of a charged AdS black hole in massive gravity. We develop a new prescription based on maximum frequencies of emission spectrum to probe the thermodynamics of black holes and get an accurate insight into its phase transition criticality. We establish a link between the thermodynamic behavior and the maximum emission frequency of the black hole for both the photons and massive bosonic modes. We show that the frequency maximizing the spectrum combined to the shadow radius can serve as a powerful physical tool to delve into the thermodynamics and phase structure of RN-AdS black holes in massive gravity.

gr-qc↗

arXiv2024

Unified Interpretation of 95 GeV Excesses in the Two Higgs Doublet type II Seesaw Model

In the search for a light Higgs boson, the ATLAS and CMS experiments have observed excesses in both the diphoton ($γγ$) and di-tau-pair ($τ^+τ^-$) decay channels at about $95$ GeV. The LEP collaboration has also previously reported an excess in the $b\bar{b}$ channel at a comparable Higgs mass. In this paper, we explore whether these excesses can be accommodated within the framework of the Two Higgs Doublet type II Seesaw Model (2HDMcT). By implementing various theoretical constraints and experimental limits on the parameter space, we first demonstrate that a light CP-even Higgs boson, $h_1$, with a mass around 95 GeV can simultaneously account for the excesses observed in the $γγ$ and $b\bar{b}$ channels, provided a Type I Yukawa texture is employed. More interestingly, our analysis shows that the three excesses in $γγ$, $b\bar{b}$ and $τ^+τ^-$ channels can well be accommodated simultaneously, reaching a $0.64 σ$ C.L. if the CP-odd Higgs boson $A_1$ is nearly mass degenerate and superposed to the light CP-even Higgs $h_1$.

hep-ph↗

arXiv2024

Activity Report on the Eighth African School of Fundamental Physics and Applications (ASP2024)

The African School of Fundamental Physics and Applications, also known as the African School of Physics (ASP), was initiated in 2010, as a three-week biennial event, to offer additional training in fundamental and applied physics to African students with a minimum of three-year university education. Since its inception, ASP has grown to be much more than a school. ASP has become a series of activities and events to support academic development of African students, teachers and faculties. We report on the eighth African School of Physics, ASP2024, organized in Morocco, on April 15--19 and July 7--21, 2024. ASP2024 included programs for university students, high school teachers and high school pupils.

physics.ed-ph↗

arXiv2024

Summary Report on the 2024 African School of Physics Program for Learners

On April 15-19, 2024, as a part of the eighth African School of Physics, ASP2024, we organized a program for learners from selected high schools in the vicinity of Marrakesh, Morocco. In this event, within a week, we reached out to over a thousand high school students, aka learners, from many high schools in the region of Marrakesh. We present a summary report on these outreach activities.

physics.ed-ph↗

arXiv2022

High Energy Physics activities in Africa: An overview

This document summarizes our best knowledge of the ongoing High Energy Physics activities in Africa. The information was primarily extracted from the first ASFAP Particle Physics day organised on November 2021 and on our working group talk presented at ACP 2021 conference on March 2022.

hep-ph↗

arXiv2022

Demystifying the fractional order phase transitions in AdS black holes

In this work, we performed a detailed study of the fractional order phase transition (FPT) for several AdS black hole prototypes [1]. Our objective is to see whether the FPT 4/3 order at critical points reported in [2] is universal. Our analysis shows two remarkable features: Firstly, the FPT is located at 4/3 order only when the black hole possesses a spherical symmetry. Secondly, this fractional order is not universal and can be altered by the geometric symmetry.

hep-th↗

arXiv2022

Activity Report of the Second African Conference on Fundamental and Applied Physics, ACP2021

The African School of Fundamental Physics and Applications, also known as the African School of Physics (ASP), was initiated in 2010, as a three-week biennial event, to offer additional training in fundamental and applied physics to African students with a minimum of three-year university education. Since its inception, ASP has grown to be much more than a school. ASP has become a series of activities and events with directed ethos towards physics as an engine for development in Africa. One such activity of ASP is the African Conference on Fundamental and Applied Physics (ACP). The first edition of ACP took place during the 2018 edition of ASP at the University of Namibia in Windhoek. In this paper, we report on the second edition of ACP, organized on March 7--11, 2022, as a virtual event.

physics.ed-ph↗

arXiv2021

The African School of Fundamental Physics and Applications Activity Report 2019-2021

The sixth edition of the African School of Fundamental and Applied Physics (ASP) was planned for Morocco in July 2020 and was referred to as ASP2020. Preparations were at an advanced stage when ASP2020 was postponed because of the COVID-19 pandemic. The three-week event was restructured into two activities in 2021 -- an online event on July 19-30, 2021 and a hybrid event on December 12-18, 2021 -- and was renamed ASP2021. At the beginning of the COVID-19 pandemic, an online lecture series was integrated into the ASP activities. The ASP mentorship program, which consists of online engagements between lecturers and assigned mentees, continued in this way. ASP alumni studied one year of COVID-19 data of ten African countries to offer insights into pandemic containment measures. In this note, we report on ASP activities since the last in-person edition of ASP in 2018 in Namibia.

physics.ed-ph↗

arXiv2020

Fingerprinting the fractional order phase transitions in AdS black holes

In this paper, we have extended and deepened the study on fractional order phase transition (FPT) of a charged AdS black hole performed in [1]. We have carried out a detailed analysis of FPT for several AdS black hole prototypes: black hole surrounded by quintessence background, 5D Gauss-Bonnet, D dimensional RN-AdS BH, and lastly Kerr black holes. We have shown that the 4/3 order FPT at critical points obtained in [1] still holds for the first three black holes systems, while for Kerr black holes, the fractional order is rather 1/3. These results suggest two remarkable features: Firstly 4/3 order phase transition can be assumed for asymptotically AdS black holes spherical solutions, secondly the fractional order is not universal and can be affected by the geometric symmetry.

hep-th↗

arXiv2020

Event reconstruction for KM3NeT/ORCA using convolutional neural networks

The KM3NeT research infrastructure is currently under construction at two locations in the Mediterranean Sea. The KM3NeT/ORCA water-Cherenkov neutrino detector off the French coast will instrument several megatons of seawater with photosensors. Its main objective is the determination of the neutrino mass ordering. This work aims at demonstrating the general applicability of deep convolutional neural networks to neutrino telescopes, using simulated datasets for the KM3NeT/ORCA detector as an example. To this end, the networks are employed to achieve reconstruction and classification tasks that constitute an alternative to the analysis pipeline presented for KM3NeT/ORCA in the KM3NeT Letter of Intent. They are used to infer event reconstruction estimates for the energy, the direction, and the interaction point of incident neutrinos. The spatial distribution of Cherenkov light generated by charged particles induced in neutrino interactions is classified as shower- or track-like, and the main background processes associated with the detection of atmospheric neutrinos are recognized. Performance comparisons to machine-learning classification and maximum-likelihood reconstruction algorithms previously developed for KM3NeT/ORCA are provided. It is shown that this application of deep convolutional neural networks to simulated datasets for a large-volume neutrino telescope yields competitive reconstruction results and performance improvements with respect to classical approaches.

astro-ph.IM↗

arXiv2020

gSeaGen: the KM3NeT GENIE-based code for neutrino telescopes

The gSeaGen code is a GENIE-based application developed to efficiently generate high statistics samples of events, induced by neutrino interactions, detectable in a neutrino telescope. The gSeaGen code is able to generate events induced by all neutrino flavours, considering topological differences between track-type and shower-like events. Neutrino interactions are simulated taking into account the density and the composition of the media surrounding the detector. The main features of gSeaGen are presented together with some examples of its application within the KM3NeT project.

astro-ph.IM↗

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↗

arXiv2017

On Naturalness in type II seesaw models and the heavy Higgs masses

Here we study naturalness problem in a type II seesaw model, and show that the Veltman condition modified (mVC) by virtue of the additional scalar charged states is satisfied at one loop within a region of the allowed parameter space of the model. The latter is severely constrained by unitarity and boundedness from below as well as by consistency with the diphoton Higgs decay data of the LHC run 1. In this context, our analysis of the naturalness condition affects dramatically the masses of heavy Higgs bosons $H^0$, $A^0$, $H^\pm$ and $H^{\pm\pm}$, reducing the ranges of variation of $m_{H^\pm}$ and $m_{H^{\pm\pm}}$ with an upper bounds at 288 and 351 GeV, respectively, while the neutral Higgs bosons $H^0$, $A^0$ are found to be almost degenerate at about 207 GeV.

hep-ph↗

arXiv2015

Naturalness in Type II seesaw model and implications for physical scalars

In this paper we consider a minimal extension to the standard model by a scalar triplet field with hypercharge $Y=2$. This model relies on the seesaw mechanism which provides a consistent explication of neutrino mass generation. We show from naturalness considerations that the Veltman condition is modified by virtue of the additional scalar charged states and that quadratic divergencies at one loop can be driven to zero within the allowed space parameter of the model, the latter is severely constrained by unitarity, boundedness from below and is consistent with the di-photon Higgs decay data of LHC. Furthermore, we analyse the naturalness condition effects to the masses of heavy Higgs bosons $H^0$, $A^0$, $H^\pm$ and $H^{\pm\pm}$, providing a drastic reduction of the ranges of variation of $m_{H^{\pm}}$ and $m_{H^{\pm\pm}}$ with an upper bounds at $288$ and $351$~GeV respectively, while predicting an almost degeneracy for the other neutral Higgs bosons $H^0$, $A^0$ at about $207$~GeV.

hep-ph↗