arXiv subjects

Md. A. Khan

Publications and source records attributed to Md. A. Khan.

8 recordsLinked to original sources

arXiv2025

Study of few $^3$He-induced nuclear fusion reactions using density-dependent double-folding complex potential

Nuclear fusion reactions at sub-barrier energies play crucial roles in many aspects of primordial nucleosynthesis in stellar objects. One of the primary aspects that plays a pivotal role in understanding the relationship between stellar evolution and nuclear reaction dynamics is the energy dependence of astronuclear observables, such as the fusion cross-section $σ$. This paper presents the results of a few $^3$He-induced nuclear fusion reactions-$^{3}$He($^3$He,2p)$^{4}$He, $^{6}$Li($^3$He,d)$^{7}$Be and $^{10}$B($^3$He,n)$^{12}$N which are investigated adopting the single-step selective resonant tunnelling model (SRTM). As an improvement over earlier works, the authors have used a microscopically derived density-dependent double-folding potential model, invoking the M3Y-Reid NN interactions, for the numerical computation of the astrophysical S-factor, $S(E)$, and the fusion cross-section, $σ$. The results of the calculations have been compared with those found in the literature. The results obtained in the present studies agree fairly with the experimentally observed results found in the literature.

nucl-th↗

arXiv2022

Study of fusion reactions of light nuclei at low energies using complex nucleon-nucleus potential function

Nuclear fusion reactions, at energies, far below the Coulomb barrier play a significant role in the synthesis of light elements in the primordial nucleosynthesis as well as in the interior of compact stellar objects. Many different kinds of nuclear reactions are occurring simultaneously inside the stellar core depending upon the density and temperature conditions of the nuclear plasma along with other relevant parameters of these stars. Nuclear fusion reactions in the energy range ($E\sim$ 1 eV to few keV) can be explained successfully by quantum mechanical tunneling through the mutual Coulomb barrier of interacting nuclei. The measurement of the cross-sections at extremely low energy is quite difficult because of the larger width of the Coulomb barrier, which results in a very small value of the reaction cross-section. Hence, any improvement in the data on astrophysical S-factors for the light nuclei fusion may give a better picture of the elemental abundance in nucleosynthesis. In this work, we have theoretically investigated the energy dependence of fusion cross-sections and astrophysical S-factors for fusion reaction of light nuclei like D-D and p-$^{11}$B using complex Gaussian nuclear potential with adjustable depth and range parameters plus the mutual Coulomb interaction of the interacting nuclei. Numerical computation of the observables is done in the framework of the selective resonant tunneling model approach. The results of our calculation are compared with those found in the literature.

nucl-th↗

arXiv2022

Resonance energy and wave functions of $^{31}$Ne: a calculation using supersymmetric quantum mechanics

In this communication, we present an efficient method for computation of energy and wave function of weakly bound nuclei by the application of supersymmetric quantum mechanics (SSQM) and bound states in continuum (BIC) technique. As a case study the scheme is implemented to the two-body ($^{30}$Ne + n) cluster model calculation of neutron-rich nucleus $^{31}$Ne. Woods-Saxon central potential with spin-orbit component is used as the core-nucleon interaction. The two-body Schrödinger equation in relative coordinate is solved numerically to get the energy and wave function of the low-lying bound states. A one-parameter family of isospectral potential (IP) is constructed from the bound state solutions following algebra of SSQM to find energies and wave functions of the resonance states. In addition to the 2p$_{3/2^-}$ (-0.33 MeV) ground state, two bound excited states: s$_{1/2}$ (-0.30 MeV), $p_{1/2}$ (-0.15 MeV) are also obtained. Few low-lying resonance states: f$_{7/2_1}$ (2.57 MeV), f$_{7/2_2}$ (4.59 MeV), f$_{5/2_1}$ (5.58 MeV), p$_{1/2_1}$(1.432 MeV), p$_{1/2_2}$ (4.165 MeV), p$_{3/2_1}$ (1.431 MeV), p$_{3/2_2}$ (4.205 MeV) are predicted. Among the predicted resonance states, the f$_{7/2^{-}}$ state having resonance energy $E_R \simeq 4.59$ MeV is in excellent agreement with the one found in the literature.

nucl-th↗

arXiv2022

Study of resonances in exotic drip-line nuclei by the use of super-symmetric quantum mechanics

In this paper, a nice theoretical scheme is presented to investigate resonant and bound states in weakly bound nuclear systems by the use of isospectral potentials together with hyperspherical harmonics expansion. In this scheme, a new potential is constructed which is strictly isospectral with the original shallow potential and has properties that are desirable to calculate resonances more accurately and elegantly. The effectiveness of the method has been checked in terms of its application to the $0^+$ resonances in the neutron-rich isotopes $^{18,20}$C in the two-neutron plus core three-body cluster model. The results are in excellent agreement with the available data.

nucl-th↗

arXiv2020

Hyperspherical few-body model calculation for cascade $Ξ$ exotic hypernuclei with reference to nuclear drip lines

In this paper, we presented the ground state energies calculated for some single and double cascade hyperon($Ξ^{-}$) hypernuclei. For hypernuclei of the type $_Ξ^{A_c+1}$X we applied $Ξ+^A_c$X two-body model and for hypernuclei of the type $_{ΞΞ}^{A_c+2}$X we adopted $Ξ+Ξ+^A_c$X three-body model. A two-term Gaussian (Isle type) potential with adjustable parameters is chosen as the $Ξ$-nucleus interaction, while a two-term Yukawa-type potential has been chosen for the $ΞΞ$ pair. In the three-body model calculation, we adopted the hyperspherical harmonics expansion (HHE) formalism. The resulting two- and three-body Schr{ö}dinger equations subject to appropriate boundary condition's have been solved numerically to get the ground-state energies and wavefunctions. Computed values are in excellent agreement with the observed ones as found in the literature. Analysis of the calculated observables indicates that the hyperons stay close to the core-nucleus. Hypernuclei formed as a result of absorption of one or more $Ξ$-hyperon(s) by a normal nucleus (bound or unbound) are found to have more stability than those formed as a result of absorption of one or more $Λ$ hyperon(s) by the same nucleus. This fact flashes towards the possibility of the existence of a valley of strange hypernuclei near the drip lines.

nucl-th↗

arXiv2018

Astrophysical S-factor for the deep sub-barrier fusion reactions of light nuclei

The cross sections for the deep sub-barrier fusion reaction of light nuclei are calculated within the theoretical framework of the selective resonant tunneling model. In this model, assumption of a complex square-well nuclear potential is invoked to describe the absorption inside the nuclear well. The theoretical estimates for these cross sections agree well with the experimentally measured values. The features of the astrophysical S-factor are derived in terms of this model. Present formalism appears to be particularly useful for the low energy resonant reactions between two charged nuclei.

nucl-th↗

arXiv2017

Few-body model approach to the lowest bound S-state of non-symmetric exotic few-body systems

Lowest bound S-state energy of Coulomb three-body systems ($N^{Z+}μ^-e^-$) having a positively charged nucleus of charge number Z ($N^{Z+}$), a negatively charged muon ($μ^-$) and an electron ($e^-$), is investigated in the framework of hyperspherical harmonics expansion method. A Yukawa type Coulomb potential with an adjustable screening parameter ($λ$) is chosen for the 2-body subsystems. In the resulting Schrödinger equation (SE), the three-body relative wave function is expanded in the complete set of hyperspherical harmonics (HH). Thereafter use of orthonormality of HH in the SE, led to a set of coupled differential equations which are solved numerically to get the energy (E) of the systems investigated.

physics.atm-clus↗

arXiv2014

Application of Homotopy Perturbation Method to an Eco-epidemic Model

In this article, we apply Homotopy Perturbation Method (HPM) for solving three coupled non-linear equations which play an important role in biosystems. To illustrate the capability and reliability of this method. Numerical example is given which confirms our analytical findings.

math.DS↗