scholarly journals The Nuclear Structure for Exotic Neutron-Rich of 42, 43, 45,47K Nuclei

2016 ◽  
Vol 13 (1) ◽  
pp. 146-154
Author(s):  
Baghdad Science Journal
Keyword(s):  
Magnetic Dipole ◽  
Electron Scattering ◽  
Dipole Moments ◽  
Exotic Nucleus ◽  
Form Factors ◽  
Model Space ◽  
Density Distributions ◽  
Plane Wave Born Approximation ◽  
Magnetic Electron ◽  
Good Agreement

In this paper the proton, neutron and matter density distributions and the corresponding root mean square (rms) radii of the ground states and the elastic magnetic electron scattering form factors and the magnetic dipole moments have been calculated for exotic nucleus of potassium isotopes K (A= 42, 43, 45, 47) based on the shell model using effective W0 interaction. The single-particle wave functions of harmonic-oscillator (HO) potential are used with the oscillator parameters b. According to this interaction, the valence nucleons are asummed to move in the d3f7 model space. The elastic magnetic electron scattering of the exotic nuclei 42K (J?T= 2- 2), 43K(J?T=3/2+ 5/2), 45K (J?T= 3/2+ 7/2) and 47K (J?T= 1/2+ 9/2) investigated through Plane Wave Born Approximation (PWBA). The inclusion of core polarization effect through the effective g-factors is adequate to obtain a good agreement between the predicted and the measured magnetic dipole moments.

scholarly journals Elastic transverse electron scattering form factors of 11Li exotic nucleus

2019 ◽  
Vol 12 (23) ◽  
pp. 65-72
Author(s):  
B. S. Hameed
Keyword(s):  
Shell Model ◽  
Electron Scattering ◽  
Exotic Nucleus ◽  
Form Factors ◽  
Model Space ◽  
Model Calculations ◽  
Plane Wave Born Approximation ◽  
The Difference ◽  
Elastic Transverse ◽  
Transverse Electron

        The elastic transverse electron scattering form factors have been studied for the 11Li   nucleus using the Two- Frequency Shell Model (TFSM) approach. The single-particle wave functions of harmonic-oscillator (HO) potential are used with two different oscillator parameters bcore and bhalo. According to this model, the core nucleons of 9Li nucleus are assumed to move in the model space of spsdpf. The outer halo (2-neutron) in 11Li is assumed to move in the pure 1p1/2, 1d5/2, 2s1/2 orbit. The shell model calculations are carried out for core nucleons using the spsdpf-interaction.  The elastic magnetic electron scattering of the stable 7Li and exotic 11Li nuclei are also investigated through Plane Wave Born Approximation (PWBA). It is found that the difference between the total form factors of unstable isotope (11Li halo) and stable isotope 7Li is in magnitude. The measured value of the magnetic moment is also reproduced.

scholarly journals Density distributions and form factors of the exotic 8B nucleus

2019 ◽  
Vol 11 (20) ◽  
pp. 25-34
Author(s):  
W. Z. Majeed
Keyword(s):  
Electron Scattering ◽  
Exotic Nucleus ◽  
Form Factors ◽  
Model Space ◽  
Matter Density ◽  
Long Tail ◽  
Density Distributions ◽  
Valence Proton ◽  
Model Approach ◽  
Proton Halo

Results of charge, neutron and matter densities and related form factors for one- proton halo nucleus 8B are presented using a two- frequency shell model approach. We choose a model space for the core of 7Be different from that of the extra one valence proton. One configuration is assumed for the outer proton to be in 1p1/2 - shell. The results of the matter density distributions are compared with those fitted to the experimental data. The calculated proton and matter density distributions of this exotic nucleus exhibit a long tail behavior, which is considered as a distinctive feature of halo nuclei. Elastic electron scattering form factors of this exotic nucleus are also studied. The effects of the proton halo on the electron scattering form factors are analyzed. The form factors of the exotic unstable 8B nucleus are compared with those of the stable 10B nucleus. The differences between the results of unstable 8B and stable 10B nuclei come from the long tail in the density distribution of the last proton.

Inelastic electric and magnetic electron scattering form factors of 24Mg nucleus: Role of g factors

2017 ◽  
Vol 26 (05) ◽  
pp. 1750032 ◽  
Author(s):  
Anwer A. Al-Sammarraie ◽  
M. L. Inche Ibrahim ◽  
Muna Ahmed Saeed ◽  
Fadhil I. Sharrad ◽  
Hasan Abu Kassim
Keyword(s):  
Experimental Data ◽  
Electron Scattering ◽  
Form Factors ◽  
Wave Functions ◽  
Matrix Elements ◽  
Model Hamiltonian ◽  
Transverse Electron ◽  
Magnetic Electron ◽  
Good Agreement

The electric and magnetic transitions in the [Formula: see text]Mg nucleus are studied based on the calculations of the longitudinal and the transverse electron scattering form factors. The universal sd-shell model Hamiltonian (USDA) is used for calculations. The wave functions of radial single-particle matrix elements are calculated using the Skyrme potential. For the longitudinal form factors, a good agreement is obtained between the calculations and the experimental data. For the transverse form factors, the effective [Formula: see text] factors are made as adjustable parameters in order to describe the experimental data.

scholarly journals Investigation of density and form factor of some F isotopes using Hartree-Fock and shell model calculations

2019 ◽  
Vol 14 (30) ◽  
pp. 158-171
Author(s):  
Wasan Z. Majeed
Keyword(s):  
Shell Model ◽  
Electron Scattering ◽  
Form Factors ◽  
Skin Thickness ◽  
Neutron Skin ◽  
Model Calculations ◽  
Hartree Fock ◽  
Density Distributions ◽  
Tail Part ◽  
Good Agreement

Structure of unstable 21,23,25,26F nuclei have been investigatedusing Hartree – Fock (HF) and shell model calculations. The groundstate proton, neutron and matter density distributions, root meansquare (rms) radii and neutron skin thickness of these isotopes arestudied. Shell model calculations are performed using SDBAinteraction. In HF method the selected effective nuclear interactions,namely the Skyrme parameterizations SLy4, Skeσ, SkBsk9 andSkxs25 are used. Also, the elastic electron scattering form factors ofthese isotopes are studied. The calculated form factors in HFcalculations show many diffraction minima in contrary to shellmodel, which predicts less diffraction minima. The long tailbehaviour in nuclear density is noticeable seen in HF more than shellmodel calculations. The deviation occurs between shell model andHF results are attributed to the sensitivity of charge form factors tothe change of the tail part of the charge density. Calculations donefor the rms radii in shell model showed excellent agreement withexperimental values, while HF results showed an overestimation inthe calculated rms radii for 21,23F and good agreement for 25,26F. Ingeneral, it is found that the shell model and HF results have the samebehaviour when the mass number (A) increase.

scholarly journals Inelastic transverse magnetic dipole electron scattering form factors in 48Ca (restricted optimum configurations)

2019 ◽  
Vol 14 (30) ◽  
pp. 9-17
Author(s):  
Firas Z. Majeed
Keyword(s):  
Magnetic Dipole ◽  
Electron Scattering ◽  
State Energy ◽  
Form Factors ◽  
Model Space ◽  
Transverse Magnetic ◽  
Excited State Energy ◽  
Inert Core ◽  
Nuclear Shell ◽  
Theoretical Results

Inelastic transverse magnetic dipole electron scattering formfactors in 48Ca have been investigated through nuclear shell modelin an excited state energy Ex= 10.23 MeV which is so called"mystery case" with different optional choices like effectiveinteraction, restricted occupation and core polarization interaction.40Ca as an inert core will be adopted and four orbits with eightparticles distributed mainly in 2p1f model space and in some extendrestricted to make sure about the major accuse about this type oftransition. Theoretical results have been constituted mainly withexperimental data and compared with some important theoreticalresults of the same transition.

scholarly journals The Electro-Excitation Form Factors for Low-Lying States of 7Li Nucleus

2010 ◽  
Vol 7 (1) ◽  
pp. 105-112
Author(s):  
Baghdad Science Journal
Keyword(s):  
Shell Model ◽  
Electron Scattering ◽  
Form Factors ◽  
Model Space ◽  
Theoretical Models ◽  
Inelastic Electron ◽  
Oscillator Shell ◽  
21.60 Cs ◽  
Configuration Mixing ◽  
Transverse Electron

The transverse electron scattering form factors have been studied for low –lying excited states of 7Li nucleus. These states are specified by J? T= (0.478MeV), (4.63MeV) and (6.68MeV). The transitions to these states are taking place by both isoscalar and isovector components. These form factors have been analyzed in the framework of the multi-nucleon configuration mixing of harmonic oscillator shell model with size parameter brms=1.74fm. The universal two-body of Cohen-Kurath is used to generate the 1p-shell wave functions. The core polarization effects are included in the calculations through effective g-factors and resolved many discrepancies with experiments. A higher configuration effect outside the 1p-shell model space, such as the 2p-shell, enhances the form factors for q-values and reproduces the data. The present results are compared with other theoretical models. PACS: 25.30.Bf Elastic electron scattering - 25.30.Dh Inelastic electron scattering to specific states – 21.60.Cs Shell model – 27.20. +n 5? A ?19

scholarly journals Blast from the past: Constraints on the dark sector from the BEBC WA66 beam dump experiment

2021 ◽  
Vol 10 (2) ◽  
Author(s):  
Giacomo Marocco ◽  
Subir Sarkar
Keyword(s):  
Proton Beam ◽  
Magnetic Dipole ◽  
Electron Scattering ◽  
Dipole Moments ◽  
Bubble Chamber ◽  
Dark Sector ◽  
Beam Dump ◽  
The Past ◽  
Scattering Events

We derive limits on millicharged dark states, as well as particles with electric or magnetic dipole moments, from the number of observed forward electron scattering events at the Big European Bubble Chamber in the 1982 CERN-WA-066 beam dump experiment. The dark states are produced by the 400~GeV proton beam primarily through the decays of mesons produced in the beam dump, and the lack of excess events places bounds extending up to GeV masses. These improve on bounds from all other experiments, in particular CHARM~II.

scholarly journals Charge density distributions and electron scattering form factors of 25Mg, 27Al and 29Si nuclei

2019 ◽  
Vol 14 (30) ◽  
pp. 129-135
Author(s):  
Lubna Abduljabbar Mahmood
Keyword(s):  
Charge Density ◽  
Explicit Form ◽  
Electron Scattering ◽  
Ground State ◽  
Density Operator ◽  
Form Factors ◽  
Body Density ◽  
Density Distributions ◽  
Tail Part

An effective two-body density operator for point nucleon systemfolded with the tenser force correlations( TC's), is produced and usedto derive an explicit form for ground state two-body charge densitydistributions (2BCDD's) applicable for 25Mg, 27Al and 29Si nuclei. It isfound that the inclusion of the two-body TC's has the feature ofincreasing the central part of the 2BCDD's significantly and reducingthe tail part of them slightly, i.e. it tends to increase the probability oftransferring the protons from the surface of the nucleus towards itscenteral region and consequently makes the nucleus to be more rigidthan the case when there is no TC's and also leads to decrease the1/ 2r 2 of the nucleus. It is also found that the effect of the TC's and theeffect of increasing the values of  on the 2BCDD's, elasticelectron scattering form factors and r2 1/ 2 are in the same directionfor all considered nuclei.

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