scholarly journals Matter Density Distributions, Root-mean Square Radii and Elastic Electron Scattering Form Factors of Some Exotic Nuclei (17B, 11Li, 8He)

2021 ◽  
Vol 19 (50) ◽  
pp. 60-69
Author(s):  
Shaimaa Ali Rahi ◽  
Gaith Naima Flaiyh

The two-neutron halo-nuclei (17B, 11Li, 8He) was investigated using a two-body nucleon density distribution (2BNDD) with two frequency shell model (TFSM). The structure of valence two-neutron of 17B  nucleus in a pure (1d5/2) state and in a pure (1p1/2) state for  11L and 8He nuclei. For our tested nucleus, an efficient (2BNDD's) operator for point nucleon system folded with two-body correlation operator's functions was used to investigate nuclear matter density distributions, root-mean square (rms) radii, and elastic electron scattering form factors. In the nucleon-nucleon forces the correlation took account of the effect for the strong tensor force (TC's). The wave functions of single particle harmonic oscillator are used with two different oscillator size parameters βc and βv, where the former is for the core (inner) orbits and the latter is for the valence (halo) orbits. The measured matter density distributions of these nuclei clearly showed long tail results. To investigate elastic electron scattering form factors the plane wave born approximation (PWBA) with two body nucleon density distribution (2BNDD's) was use.

2019 ◽  
Vol 12 (24) ◽  
pp. 100-109
Author(s):  
Ghaith N. Flaiyh

The nucleon momentum distributions (NMD) for the ground state and elastic electron scattering form factors have been calculated in the framework of the coherent fluctuation model and expressed in terms of the weight function (fluctuation function). The weight function has been related to the nucleon density distributions of nuclei and determined from theory and experiment. The nucleon density distributions (NDD) is derived from a simple method based on the use of the single particle wave functions of the harmonic oscillator potential and the occupation numbers of the states. The feature of long-tail behavior at high momentum region of the NMD has been obtained using both the theoretical and experimental weight functions. The observed electron scattering form factors for 48Ti and 54Fe nuclei are in reasonable agreement with the present calculations throughout all values of momentum transfer q.


2019 ◽  
pp. 1286-1296
Author(s):  
Rafah I. Noori ◽  
Arkan R. Ridha

In this work, the nuclear density distributions, size radii and elastic electron scattering form factors are calculated for proton-rich 8B, 17F, 17Ne, 23Al and 27P nuclei using the radial wave functions of Woods-Saxon potential. The parameters of such potential for nuclei under study are generated so as to reproduce the experimentally available size radii and binding energies of the last nucleons on the Fermi surface.


1969 ◽  
Vol 24 (5) ◽  
pp. 858-859 ◽  
Author(s):  
Hans Alfred Bentz

Abstract From elastic electron scattering between 30 and 60 MeV, the following essentially model independent rms charge radii (fm) have been deduced: 2.395 + 0.028 (12C) ; 2.492 + 0.033 (14N) ;2.666± 0.033 (16O). An improved value for 9Be is (2.43 ±0.08) fm.


2019 ◽  
Vol 28 (03) ◽  
pp. 1950015
Author(s):  
Xiaoyong Guo ◽  
Zaijun Wang ◽  
Tianjing Li ◽  
Jian Liu

We construct a scheme to calculate the charge form factors for the elastic electron scattering. Our calculation is based on the relativistic eikonal approximation and the Skyrme–Hartree–Fock equation. To perform our calculation and benchmark the results, eight model nuclei with available experimental data: [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] are considered. For the comparison, the charge form factors calculated by the relativistic mean-field (RMF) model are also provided. Parameter set SLy5 is utilized for the Skyrme force, and the set NL3 is applied for the RMF model. It has been confirmed that combining of a nonrelativistic treatment for the target nucleus with a relativistic treatment for the incident electron may work better to reach highly descriptive and predictive results similar to the pure relativistic treatment. The results of this work are also useful for future experiments to test different inputs of densities for a specific nucleus.


2019 ◽  
Vol 13 (28) ◽  
pp. 68-81
Author(s):  
A. R. Ridha

The ground state proton, neutron and matter densities andcorresponding root mean square radii of unstable proton-rich 17Neand 27P exotic nuclei are studied via the framework of the twofrequencyshell model. The single particle harmonic oscillator wavefunctions are used in this model with two different oscillator sizeparameters core b and halo , b the former for the core (inner) orbitswhereas the latter for the halo (outer) orbits. Shell model calculationsfor core nucleons and for outer (halo) nucleons in exotic nuclei areperformed individually via the computer code OXBASH. Halostructure of 17Ne and 27P nuclei is confirmed. It is found that thestructure of 17Ne and 27P nuclei have 25 / 2 (1d ) and 1/ 2 2s -dominantconfigurations, respectively. Elastic electron scattering form factorsof these exotic nuclei are also studied using the plane wave Bornapproximation. Effects of the long tail behavior of the proton densitydistribution on the proton form factors of 17Ne and 27P areanalyzed. It is found that the difference between the proton formfactor of 17Ne and that of stable 20Ne (or of 27P and that of stable31P) comes from the difference in the proton density distribution ofthe last two protons (or of the last proton) in the two nuclei. It isconcluded that elastic electron scattering will be an efficient tool (inthe near future) to examine proton-halo phenomena of proton-richnuclei.


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