Search

Most of the current experimental searches for charged Higgs bosons at the Large Hadron Collider (LHC) concentrate upon the $tb$ and $\tau\nu$ decay channels. In the present study, we analyze instead the feasibility of the bosonic decay channel $W^{\pm *} h$, with the charged gauge boson being off-shell and $h$ being a neutral light Higgs boson, which decays predominantly into $b\bar{b}$. We perform a Monte Carlo (MC) analysis for the associate production of a charged Higgs with such a light neutral one, $pp\to H^\pm h$, at the LHC followed by the aforementioned charged Higgs boson decay, which leads to a $W^{\pm *} +4b$ final state. The analysis is performed within the 2-Higgs Doublet Model (2HDM) with Yukawa texture of Type-I. We take into account all available experimental constraints from LEP, Tevatron and the LHC as well as the theoretical requirements of self-consistency of this scenario. In order to study the full process $pp \rightarrow H^{\pm} h \rightarrow W^{\pm *} h h \rightarrow \ell^\pm \nu+ 4b$ ($\ell=e,\mu$), we provide several Benchmark Points (BPs) amenable to further analysis, with $M_{H^\pm}+M_{b} < M_{t}$, for which we prove that there is a strong possibility that this spectacular signal could be found at the LHC with center of mass energy 14 TeV and luminosity 300 $\rm{fb}^{-1}$., Comment: 20 pages, 9 figures, 7 tables

In this contribution, the likelihood of seeing charged Higgs and $W$ boson production in the context of 2HDMs type-I and type-X at the LHC is examined, assuming that either $h$ or $H$ resembles the detected resonance around $\sim 125$ GeV. We consider the possibility of the charged Higgs boson decays channels through $H^\pm \to W^\pm h_i / A$, focusing on the $b\bar{b}$ and $\tau\tau$ decays of $h_i$ and $A$. In both type-I and type-X insights of the 2HDMs, we investigate the potential fingerprints resulting from the previously mentioned charged Higgs production and decay. We find in our study that these signatures can have sizable rates at low $\tan\beta$ as long as the condition $M_{H^\pm} < m_t - m_b$ is met. As a result, we propose the $bb$ and $\tau\tau$ final states associated with $WW$ as an encouraging experimental avenue that would complement the LHC search for a charged Higgs boson., Comment: 8 pages, 5 figes, 8th Symposium on Prospects in the Physics of Discrete Symmetries (DISCRETE 2022)

We analyse a light charged Higgs boson in the 2-Higgs Doublet Model (2HDM) Type-I, when its mass satisfies the condition MH±< Mt + Mb and the parameter space is consistent with theoretical requirements of self-consistency as well as the latest experimental constraints from Large Hadron Collider (LHC) and other data. Over such a parameter space, wherein the Standard Model (SM)-like state discovered at the LHC in 2012 is the heaviest CP-even state of the 2HDM, it is found that the decay modes of the charged Higgs boson are dominated by H±→ W±(∗)h. Furthermore, the light neutral Higgs boson h dominantly decays into two photons. Under these conditions, we find that the production and decay process pp → H±h → W±(∗)hh → ℓνℓ + 4γ (ℓ = e, μ) is essentially background free. However, since the W±(∗) could be largely off-shell and the h state is very light, so that both the lepton coming from the former and the photons coming from the latter could be rather soft, we perform here a full Monte Carlo (MC) analysis at the detector level demonstrating that such a W± + 4γ signal is very promising, as it would be yielding significant excesses at the LHC with an integrated luminosity of L = 300 fb−1 at both $$ \sqrt{s} $$ s = 13 and 14 TeV.

Various physical properties (electronic, optical and thermoelectric) of cubic perovskite oxides $SrXO_3\; (X=Sc,\; Ge,\; Si)$ are investigated by using the density functional theory (DFT) within Wien2k code. This code is based on different approximations such as generalized gradient approximation GGA, PBEsol, LDA, WC and the modified Becke-Johnson exchange potentials (mBJ, nmBJ and unmBJ). Structural properties and the optimization have been calculated using PBEsol functional which showed a significant results that are in good agreement with the experimental ones. The results for physical properties such as electronic, thermoelectric and optical are analyzed in detail by using the nmBJ approximation. The obtained results present an opening gap for $SrSiO_3$, $SrGeO_3$ and a metallic behavior for $SrScO_3$. An average of transmittance which is about $94\%$ to $97\%$ was observed in the range of visible light. The increase of electrical conductivity with temperature confirms the effect of thermal agitation on the concentration of charges carriers using BolzTrap Package. Lastly a phonon dispersion was made and show that for $X=\; Ge$ and $Si$, the structure is relatively stable while $SrScO_3$ is dynamically unstable. These results prove the ability that these materials can be exploited in many applications and manufacturing of optoelectronics for Sensors., 22 pages, 16 figures

In this research paper, we investigate the decay of the proton into neutron, positron and electron neutrino in the presence of an external electromagnetic field with circular polarization. Different physical quantities related to this decay process, such as proton's decay rate and its lifetime, are calculated based on the S-matrix approach. The proton and positron are treated as Dirac-Volkov states, while the neutron and electron neutrino are free-states. We have found that, though it can not occur in vacuum, the proton's decay process into neutron, positron and electron neutrino becomes possible in the presence of laser field with high intensities near or close to the Schwinger limit. In addition, near this limit and for some frequencies, the proton's lifetime can be comparable to that of the neutron, and the required laser strength, from which this decay becomes possible, depends on the chosen laser source., 10 pages, 2 figures

In both absence and presence of a circularly polarized monochromatic electromagnetic pulse, we have analyzed the electron-nucleon scattering process, where the nucleon is assumed to be spinless with a spherical shape. We have provided the theoretical calculation of the differential cross section (DCS) by using the Dirac-Volkov formalism. This research paper aims to provide two comparisons: We first compare the DCS in the absence of the laser field with its corresponding laser-assisted DCS. A second comparison is made between the electron-proton and electron-neutron scattering processes to study the effect of the laser on both processes. The results obtained about the effect of the laser field on the DCS and the electric form factor have been discussed for both scattering processes. We have found that the DCS is reduced when the laser field is applied for both processes. In addition, the form factor is also decreased by raising the incident electron energy in electron-proton scattering, but it increases in electron-neutron scattering. Moreover, the form factors for both scattering situations are unchanged by raising the laser field strength up to $10^{8}\,V/cm$., 17 pages, 6 figures

We investigate the light charged Higgs boson production via $pp \rightarrow H^\pm h$ at the Large Hadron Collider (LHC) in the Two-Higgs Doublet Model (2HDM) type-I. By focusing on a scenario where $H$ is the observed Higgs boson of mass 125 GeV, we study the aforementioned Higgs boson production channel and explore its bosonic decay $H^\pm \rightarrow W^\pm h$. The latter can have a sizable rate that possibly dominates, over the fermionic decay channels, in several regions of the viable parameter space. We demonstrate that the production process $pp \rightarrow H^\pm h$ followed by $H^\pm \rightarrow W^\pm h$ could be the most promising experimental avenue to search for light $H^\pm$ at the LHC., 6 pages, 2 figures, talk given at First Pan-African Astro-Particle and Collider Physics Workshop, 21-23 March 2022; v2 added affiliation and email address

In the centre of mass frame, we have investigated the process of Higgs production in association with a pair of fermions, $e^{+}e^{-}\rightarrow f\bar{f} H$, at the leading order inside an intense electromagnetic field with circular polarization. Our analytical calculations are based on the Narrow Width Approximation (NWA), which is valid in the leading order. We have considered only the initial particles inside the laser field as a first step. In the second part, we have embedded both initial and final particles in the laser field. We have analyzed the angular distribution of the produced Higgs boson as a function of the laser parameters in both cases. We have found that in the case where both initial and final particles are embedded in the laser field, the order of magnitude of the differential cross-section of the process $e^{+}e^{-}\rightarrow\mu^{+}\mu^{-}H$ is reduced more significantly, while that of the process $e^{+}e^{-}\rightarrow\nu\bar{\nu}H$ is enhanced., Comment: 7 pages, 4 figures

We analyze a new signature of a charged Higgs boson in the Type-I realization of the 2-Higgs Doublet Model (2HDM), where the mass of the charged Higgs boson satisfies the condition $M_{H^{\pm}}, Comment: Talk presented at the Charged Higgs Online workshop, 30-31 August 2021. 6 pages, 16 figures

Choosing a specific direction for the propagation of laser field waves often presents a challenge for researchers studying laser-assisted ultrafast quantum processes. They are faced with the question of why exactly this direction and not another. This paper resolves the discussion in this issue regarding decay processes. Therefore, we study theoretically the pion decay process in the presence of a circularly polarized laser field propagating along an arbitrary general direction. Using the first Born approximation and the Dirac-Volkov states for charged particles, we derive an analytic expression for the decay rate. The direction of the laser field was found to have no significant effect on the nature of the result obtained. This study generalizes the results found for a field with a wave vector along the $z$-axis in a recent paper (Phys Rev D 102:073006, 2020). This paper will serve as a justification for the choice of a specific direction for the laser field in laser-assisted decay processes. The effect of the laser field on the total decay rate has also been reported and discussed., 10 pages, 5 figures, 2 tables

We analyse a light charged Higgs boson in the 2-Higgs Doublet Model (2HDM) Type-I, when its mass satisfies the condition $M_{H^{\pm}} < M_{t}+M_{b}$ and the parameter space is consistent with theoretical requirements of self-consistency as well as the latest experimental constraints from Large Hadron Collider (LHC) and other data. Over such a parameter space, wherein the Standard Model (SM)-like state discovered at the LHC in 2012 is the heaviest CP-even state of the 2HDM, it is found that the decay modes of the charged Higgs boson are dominated by $H^{\pm} \rightarrow W^{\pm *} h$. Furthermore, the light neutral Higgs boson $h$ dominantly decays into two photons. Under these conditions, we find that the production and decay process $ p p \to H^\pm h \to {W^\pm}^{(*)} h h \to l \nu_{l} + 4 \gamma$ ($l=e,\mu$) is essentially background free. However, since the $W^{\pm(*)}$ could be largely off-shell and the $h$ state is very light, so that both the lepton coming from the former and the photons coming from the latter could be rather soft, we perform here a full Monte Carlo (MC) analysis at the detector level demonstrating that such a $W^{\pm} + 4\gamma$ signal is very promising, as it would be yielding significant excesses at the LHC with an integrated luminosity of $L=$ 300 $fb^{-1}$ at both $\sqrt{s}= 13$ and $14 ~\text{TeV}$., Comment: 21 pages, 18 figures