بحوث سكوبس — سارة مهدي عبيد جبر الشريفي

This study conducts an analysis of Gamow-Teller (GT) transition strengths across nuclei in the p, psd , and sd shells using nuclear shell-model analysis. The CKII and PSDMK interactions were applied for p and psd -shell nuclei, while USDA and USDB interactions were used for the sd shell. Transitions examined include ¹³C→¹³B, ¹³C→¹³N, ¹³O→¹³N, ²³Na→²³Mg, and ²³Na→²³Ne. Theoretical B(GT) values and summed strengths (∑B(GT)) were computed and compared to experimental results from β-decay studies and charge-exchange reactions. After applying a quenching factor of 0.67, the calculations align well with observations, demonstrating the robustness of the selected effective interactions and the shell-model framework in modeling GT transitions. Copyright © 2025. Published by Elsevier B.V.

This research examines fusion reaction cross-section (σfus), barrier distribution and (Dfus) in 35Cl+51V, 19F+54Fe, 20Ne+40Ca utilizing semiclassical and quantum mechanical methods. Fusion reactions are complicated by nuclear structure, interaction potentials, and channel couplings. This study models relative motion between interacting nuclei using the WKB approximation and intrinsic structural effects using the Continuum Discretized Coupled Channel (CDCC) technique. Nuclear coupling effects on reaction processes are examined, focusing on how they change fusion barriers and fusion probabilities at different energy levels. Coupled-channel computations include excitation states, transfer channels, and deformation effects to explain nuclear dynamics. Nuclear interactions' effects on fusion enhancement or suppression are assessed by comparing theoretical predictions with experimental results. Results show that channel coupling effects considerably alter fusion cross-sections and barrier distributions, especially at near- and sub-barrier energies. The semiclassical method helps explain reaction dynamics, while quantum mechanical models better describe nuclear interactions. This work emphasizes the need of sophisticated theoretical models in improving fusion reaction predictions and understanding nuclear structure and reaction mechanisms. © Published under licence by IOP Publishing Ltd.

The C2 and C4 longitudinal form factors for the first excited (21+) and (41+) states in the even-even Palladium isotopes (104Pd, 106Pd, 108Pd, 110Pd) and 90Zr are compared in this work. We use three different nuclear potentials (Skyrme Sk35, Woods-Saxon (WS), and Harmonic Oscillator (HO)) in our theoretical calculations and compare them with real electron scattering data. The strengths and limits of each potential in explaining the observed form factors for quadrupole and hexadecapole transitions over a variety of nuclei are clarified by this comparison. Our research shows that the Skyrme Sk35 interaction, which suggests a more accurate description of the underlying transition density, often gives the most consistent agreement with experimental data, especially at greater momentum transfers. The observed discrepancies, particularly for C4 transitions and higher momentum transfers, highlight the difficulties in accurately modelling higher multipolarity excitations and point to the need for more sophisticated theoretical treatments that include effects other than simple mean-field descriptions, such as core polarization and meson exchange currents. © Published under licence by IOP Publishing Ltd.

In the present work, the inelastic electron scattering for longitudinal and transverse form factors of 65Cu and 71Ga nuclei lies in the fp-shell region are studied in the framework of the shell model. The calculation is performed in the (1f5/2, 2p3/2, 2p1/2, 1g9/2) model space using jun45 effective interaction. The wavefunctions employed to conduct the shell model calculations are extracted from the jun45 effective interaction for these nuclei with the jj44 shell model space and (Sk35−Skzs ∗) residual interaction to evaluate the interactions matrix element between initial and final states. The effective charges used to account for the core-polarization (CP) effect are created using calculations of microscopic perturbations that include intermediate one-particle, one-hole excitation from the core and the model space (MS) orbits into all upper orbits with nℏω excitations following the same approach done in [Radhi et al. in Euro. Phys. J. A 50:1–9, 2014]. To account for the (CP) effects contribution, the inelastic form factor is obtained by employing the shape of Tassie and Bohr–Mottelson models with appropriate proton and neutron effective charges. The calculated form factors were compared with available experimental data. © 2022, The Korean Physical Society.

The challenge in studying fusion reaction when the projectile is neutron or proton rich halo nuclei is the coupling mechanism between the elastic and the breakup channel, therefore the motivation from the present calculations is to estimate the best coupling parameter to introduce the effect of coupled-channels for the calculations of the total cross section of the fusion σfus, the barrier distribution of the fusion Dfus and the average angular momentum 〈L〉 for the systems 6He+206Pb, 8B+28Si, 11Be+209Bi, 17F+208Pb, 6He+238U, 8He+197Au and 15C+232Th using quantum mechanical approach. A quantum Coupled-Channel Calculations are performed using CC code. The predictions of quantum mechanical approach are comparable with the measured data that is available. Above and below the Coulomb barrier, comparison of theoretical calculations of quantum mechanical with the relevant measured data demonstrates good agreement. © 2023 University of Baghdad. All rights reserved.

Background and objectives: The investigation of heavy-ion (HI) induced fusion processes in order to comprehend the many mechanisms involved in these reactions has long been a focus of nuclear physics. The complicated structure and behavior of projectile and target nuclei with various projectile energy allows us to define the reaction process and may aid in the investigation of the potential of creating superheavy elements (SHE) in the laboratory. Methods: The semiclassical and full quantum mechanical complete fusion cross section calculations σfus and the distribution of the fusion barrier Dfus for the systems12C+50Ti,15N+56Fe,16O+63Cu and40Ar+27Al. The calculations have been carried out by using SCF code for semiclassical and CC code for quantum mechanical calculations. To account for the target and projectile relative motion, we modified these codes. The fusion barrier distribution to be calculated directly from this code by subroutines written in Fortran language and added to the main code. The coupled-channel is considered by taking two channels only due to the difficulty of solving coupled differential equations. Results: The obtained results for σfus and the Dfus for the studied systems were compared to the related measured data and discussed. Conclusion: The semiclassical method used to describe the fusion reaction agrees very well with the quantum method and with the measured data and we can conclude that this semiclassical method can be used as alternative to quantum method to study the fusion reaction. © 2023 University of AlKafeel.

The theoretical calculations of the shell model were carried out to study the levels of energy and the probabilities of the reduced electric transition B(E2;0g.s+→21+) for the even-even 132-134Te by utilizing the model spaces jj55pn with the effective interaction sn100pn and jj56pn model space with three effective interactions kh5082, cw5082 and cwg. A modification of the single particle energies has been done for the original effective interactions used in the present work leads to new codenamed interactions sn100pnm, khm5082, cwm5082 and cwgm. These modified effective interactions were also employed in our calculation which leads to a significant contribution on the calculation of the excitation energy levels. Comparison shows very good agreement between theoretical calculations and the measured data and with the previous theoretical work. © 2023 Author(s).

In the present study, the calculations of the shell model based on large-scale unrestricted fp-model space have been conducted to study the low-lying energy levels and Gamow-Teller B(GT) transition strengths for the transitions (42Ca→42Sc, 42Sc→42Ti, 45Sc→45Ca, 45Ti→45Sc,45V→45Ti) lying in the fp-shell region. The calculations of the yrast levels and Gamow-Teller B(GT) transition strengths were compared with the related measured data. The low-lying energy levels were reasonably reproduced for the studied nuclei. The spin and parity of the unconfirmed energy levels for some studied nuclei have been confirmed. The calculated B(GT) transition strengths of Gamow-Teller (GT) for the selected isotopes lie in the fp-shell region agree very well with the measured data extracted from (3He, t), (3He, t)*, (t,3He), (t, 3He+γ), and (p, n) reactions. © 2022 University of Kerbala.

The Gamow–Teller (GT) strength transitions in nuclear structures and astrophysical processes proved to be very important to understand the mechanisms of formation of neutron stars and black holes, therefore the GT transitions in the46Ti!46V,47Ti!47V,48Ti!48V, and50Cr!50Mn charge-exchange reactions have been studied. The shell model calculations have been carried out in the fp-model space without any restrictions using the GXFP1A, KB3G, and FPD6 effective interactions. The calculation of the GT distribution is compared with recent available experimental data. The theoretical calculations are in reasonably good agreement with the experimental GT distributions and with the summed transition strengths B(GT). For the individual transformations we have reached a qualitative agreement, while the measured cumulative transformation strengths are closely matched by the observed ones. © 2021, Canadian Science Publishing. All rights reserved.

This study focuses on using a semi-classical and quantum mechanical approach based originally on the theory of Winther and Alder that is used to explain the Coulomb excitation. This approach is called the coupled channels with continuum-discretised (CCCD), where the semi-classical and quantum models were used to investigate the channel coupling effects on the determination of the cross section for fusion σfus (mb) and the distribution of the fusion barrier Dfus (mb/MeV) for systems 14N+59Co, 16O+64Ni and 18O+64Ni. The comparison between the results of the semi-classical and quantum mechanical models along with the corresponding experimental data shows clearly that the adopted semi-classical model is very competitive to the quantum mechanical model and can be considered as efficient approach to study the properties of the fusion reactions. © 2020 Inderscience Enterprises Ltd.