arXiv subjects

H. A. Alhendi

Publications and source records attributed to H. A. Alhendi.

17 recordsLinked to original sources

arXiv2017

Rare $Λ_{b}\to Λ\ell^{+}\ell^{-}$ decay in the two-Higgs doublet model of type-III

The rare exclusive dileptonic $Λ_{b}\to Λ\ell^{+}\ell^{-}$ $(\ell =μ, τ)$ decays are investigated in the general two-Higgs-doublet model of type III. A significant enhancement to the branching ratios, differential branching ratios, leptons forward-backward asymmetry, and the $Λ$ baryon polarizations over the standard model is obtained. Measurements of these quantities will be useful for establishing the two-Higgs doublet model.

hep-ph↗

arXiv2016

The Higgs Boson Mass from Three-loop Effective Potential of Massless Standard Model

The effective potential of massless standard model (SM) is calculated up to three-loop order. The stability of the effective potential and the Higgs boson mass are investigated up to three-loop order. We found that, Higgs boson mass $m_{H}$ of one-loop order is large. The two-loop and three-loop results are not appreciably different from each other. The two-loop and three-loop radiative corrections have led to an improvement of Higgs boson mass and the value of the scalar coupling. For the value $m_{t}=170$ GeV at the energy scale $μ\approx 5.68\times10^2$GeV, we get $m_{H2-loop}\approx 125.4$ GeV. At the energy scale $μ\geq28\times10^2$, the scalar coupling $λ$ at two-loop becomes negative and leads to metastable vacuum while the three-loop level is stable even at high $μ$ $\approx 10^{19}$ GeV. For the larger $μ$-range $(3 \times 10^{3} \text{GeV}\leq μ\leq 20 \times 10^{3} \text{GeV})$ spontaneous symmetry breaking for one-loop and three-loop occurs at approximately the same scalar coupling values. We get $m_{H1-loop}\approx 126.14$ GeV at $μ\approx 6.5 \times 10^{3}$ GeV while for three-loop $m_{H3-loop}\approx 126$ GeV at $μ\approx 20 \times 10^{3}$ GeV.

hep-ph↗

arXiv2015

Strong decay constants of heavy tensor mesons in light cone QCD sum rules

Strong decay constants of the heavy tensor to heavy pseudoscalar (vector) and light pseudoscalar mesons are estimated within the light cone QCD sum rules. It is obtained that the values of these coupling constants are very strongly dependent on the choice of the Lorentz structure. Moreover, using these strong coupling constants the corresponding decay widths are calculated.

hep-ph↗

arXiv2015

Inhomogeneous and Homogeneous Renormalization Group Equations for the Effective Potential

The inhomogeneous renormalization group equation for the effective potential is rederived. It is shown that when the effective potential is normalized by the normalization condition on the generating functional, its renormalization group equation is homogeneous. This is demonstrated in the case of massive $ϕ^4$-theory. We also show that for the case of spontaneous symmetry breaking, the normalized effective potential is completely different from the symmetric case, though the two cases satisfy the same RGE with the same RG-functions. It is concluded that the vacuum energy density arises only in the case of SSB.

hep-ph↗

arXiv2010

Higgs boson self coupling from two-loop analysis

The scale invariant of the effective potential of the standard model at two-loop is used as a boundary condition under the assumption that the two-loop effective potential approximates the full effective potential. This condition leads with the help of the renormalization group functions of the model at two-loop to an algebraic equation of the scalar self coupling with coefficients that depend on the gauge and the top quark couplings. It admits only two real positive solutions. One of them, in the absence of the gauge and top quark couplings, corresponds to the non-perturbative ultraviolet fixed point of the scalar renormalization group function and the other corresponds to the perturbative infrared fixed point. The dependence of the scalar coupling on the top quark and the strong couplings at two-loop radiative corrections is analyzed.

hep-ph↗

arXiv2009

Description of Superdeformed Nuclei in the A~190 Region by Generalized Deformed su_{q}(2)

The generalised deformed su_{q}(2) model is applied to 79 superdeformed bands in the region A~190. The transition energies and the moments of inertia are calculated within the model, Its validity is investigated by comparing it with the experimental data. Both the standard su_{q}(2) and the generalized one fail to account for the uprising and the downturn of the dynamic moment of inertia. Both models, however, show remarkable agreement with the available experimental data at low angular frequancy (hw <= 0.25MeV).

nucl-th↗

arXiv2008

Textures with two traceless submatrices of the neutrino mass matrix

We propose a new texture for the light neutrino mass matrix. The proposal is based upon imposing zero-trace condition on the two by two sub-matrices of the complex symmetric Majorana mass matrix in the flavor basis where the charged lepton mass matrix is diagonal. Restricting the mass matrix to have two traceless sub-matrices may be found sufficient to describe the current data. Eight out of fifteen independent possible cases are found to be compatible with current data. Numerical and some approximate analytical results are presented.

hep-ph↗

arXiv2007

The Cosmology of Tetradic Theory of Gravitation

We consider a special class of the tetrad theory of gravitation which can be considered as a viable alternative gravitational theories. We investigate cosmological models based on those theories by examining the possibility of fitting the recent astronomical measurement of supernova Ia magnitude versus shift. Our investigations result in a reasonable fit for the supernova data without introducing a cosmological constant. Thus, cosmological models based on tetradic theory of gravitation can provide alternatives to dark energy models.

gr-qc↗

arXiv2005

Spectrum of One-Dimensional Anharmonic Oscillators

We use a power-series expansion to calculate the eigenvalues of anharmonic oscillators bounded by two infinite walls. We show that for large finite values of the separation of the walls, the calculated eigenvalues are of the same high accuracy as the values recently obtained for the unbounded case by the inner-product quantization method. We also apply our method to the Morse potential. The eigenvalues obtained in this case are in excellent agreement with the exact values for the unbounded Morse potential.

quant-ph↗

arXiv2005

Backbending phenomena in light nuclei at A~60 mass region

Recent studies of the backbending phenomenon in medium light weight nuclei near A~60 expanded greatly our interest about how the single particle orbits are nonlinearly affected by the collective motion. As a consequence we have applied a modied version of the exponential model with the inclusion of paring correlation to describe the energy spectra of the ground state bands and/or the backbending phenomenon in mass region at A~60. A firm conclusion is obtained concerning the successful validity of the proposed modified model in describing the backbending phenomenon in this region. Comparison with different theoretical descriptions is discussed.

nucl-th↗

arXiv2005

High-Precision Numerical Determination of Eigenvalues for a Double-Well Potential Related to the Zinn-Justin Conjecture

A numerical method of high precision is used to calculate the energy eigenvalues and eigenfunctions for a symmetric double-well potential. The method is based on enclosing the system within two infinite walls with a large but finite separation and developing a power series solution for the Schr$\ddot{o}$dinger equation. The obtained numerical results are compared with those obtained on the basis of the Zinn-Justin conjecture and found to be in an excellent agreement.

quant-ph↗

arXiv2005

Nuclear Structure Study of Some Actinide Nuclei

A modified version of the previously proposed exponential model with pairing attenuation for the well deformed even-even nuclei has been applied to predict the energy levels of doubly even actinide nuclei. Satisfactory results are obtained by that model as compared with the experimental results. The backbending phenomena are successfully described and discussed. A further comparison with the main previous models has been undertaken to confirm its validity in the heavy nuclei region.

nucl-th↗

arXiv2004

Improved Exponential model with pairing attenuation and the backbending phenomenon

A modified version of the exponential model with paring attenuation is proposed, and used to describe successfully the backbending of the moment of inertia, in even-even nuclei, not only in well-deformed nuclei but also in slightly deformed nuclei. The model remarkably fits good the experimental observation with a few parameters.

nucl-th↗

arXiv2004

Symmetric Triple Well with Non-Equivalent Vacua: Instantonic Approach

We show that for the triple well potential with non-equivalent vacua, instantons generate for the low lying energy states a singlet and a doublet of states rather than a triplet of equal energy spacing. Our energy splitting formulae are also confirmed numerically. This splitting property is due to the presence of non-equivalent vacua. A comment on its generality to multi-well is presented.

quant-ph↗

arXiv2004

QED radiative corrections for elastic e(mu)p scattering in hadronic variables

A numerical analysis of QED radiative corrections for elastic e(mu)p cattering in hadronic variables at energies of the current experiment at JLab is performed. The explicit formulas from the review of Akhundov et al. resulting from the integration over the phase space of leptonic variables plus photon are used to obtain the values of the cross sections and the radiative correction factor for unpolarized lepton-proton scattering. Our numerical results agree with the corresponding results arising from the formulas of Afanasev et al.

hep-ph↗

arXiv2004

Symmetric Triple Well with Non-Equivalent Vacua: Simple Quantum Mechanical Approach

The structure of the energy levels in a deep triple well is analyzed using simple quantum mechanical considerations. The resultant spectra of the first three energy levels are found to be composed of a ground state localized at the central well and the two other states are distributed only among the left and right well in anti-symmetric and symmetric way respectively. Due to the tunneling effects the energy eigenvalue of the ground state is approximately equal to the ground state energy for a harmonic oscillator localized at the central well, while the two others are nearly degenerate with approximate values equal to the ground state energy of a harmonic oscillator localized at the left or right well. The resulting pattern of the spectra are confirmed numerically. The failure of the instantonic approach recently applied for predicting the correct spectra is commented

quant-ph↗

arXiv2003

Spectrum of One-Dimensional Multiple Well Oscillators

We apply power series expansion to symmetric multi-well oscillators bounded by two infinite walls. The spectrum and expectation values obtained are compared with available exact and approximate values for the unbounded ones. It is shown that the method is capable of producing to a high accuracy the eigenvalues, eigenfunctions, and the expectation values $ $ of the corresponding unbounded ones as the separation between the two infinite walls becomes large.

quant-ph↗