We employ a simple effective nucleon-nucleon interaction for sd-shell model calculations derived from the Reid soft-core potential folded with two-body correlation functions which take account of the strong short-range repulsion and large tensor component in the Reid force. Shell model calculations for ground and low lying energy states of neutron rich oxygen isotopes 18-28O are performed using OXBASH code. Generally, this interaction predicts correct ordering of levels, yields reasonable energies for ground states of considered isotopes and predicts very well the newly observed excitation energy of
in 26O. Besides, it produces reasonable energy spectra for 23-27O and compressed energy spectra for 18-22O isotopes. This is mainly due entirely to defects in the
diagonal matrix elements of employed interaction. To improve the present calculations, we modify the interaction through replacing the 14 diagonal matrix elements of
with those of the USD interaction. Mostly, our modified interaction predicts well the ordering of levels, the ground state energies and low lying energy spectra for all selected oxygen isotopes. The modified interaction confirms the location of the neutron drip line at
and also identifies the presence of the shell gap at
and
which proves the doubly magic behavior of 22O and 24O. The spins in 24O of several excitation energies around 7.5 MeV are predicted by our interactions. The calculated results obtained with the modified interaction are very close to those obtained with the empirical interactions of USDB and WPN.
The two body model of (Core+n) within the radial wave functions of the cosh potential has been used to investigate the ground state features such as the proton, neutron and matter densities, the root mean square (RMS) nuclear proton, neutron, charge and mass radii of unstable neutron-rich 14B, 15C, 19C and 22N nuclei. The calculated results show that the two body model with the radial wave functions of the cosh potential succeeds in reproducing neutron halo in these nuclei.
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The ground state proton, neutron, and matter density distributions and corresponding root-mean-square (rms) of P19PC exotic nucleus are studied in terms of two-frequency shell model (TFSM) approach. The single-particle wave functions of harmonic-oscillator (HO) potential are used with two different oscillator parameters bRcoreR and bRhaloR. According to this model, the core nucleons of P18PC nucleus are assumed to move in the model space of spsdpf. The shell model calculations are carried out for core nucleons with w)20(+ truncations using the realistic WBP
interaction. The outer (halo) neutron in P
19
PC is assumed to move in the pure 2sR1/2R-
orbit. The halo structure in P
19
PC is confirmed with 2sR1/2R-dominant c
The longitudinal electron scattering form factors and the electric quadrupole moments are calculated for the states with Jπ T= 3+0 (ground state) and 1+ 0 (583keV excited state) of 22Na and Jπ T= 3+2 (ground state) of 26Na. Shell model calculations are based on USDA, USDB and Wildenthal interactions. The exact center of mass correction is included in Born approximation picture to generate the longitudinal form factors. The core polarization (CP) effect with the values of effective nucleon charges ep=1.35, en= 0.35, with Bohr Mottelson formula gave a good agreement with the measured electric quadrupole moments. The structure of th
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The ground-state properties of exotic 18N and 20F nuclei, including the neutron, proton and matter densities and related radii are investigated using the two-body model of within Gaussian (GS) and Woods Saxon (WS) wave functions. The long tail is evident in the computed neutron and matter densities of these nuclei. The plane wave Born approximation (PWBA) is calculate the elastic form factors of these exotic nuclei. The variation in the proton density distributions due to the presence of the extra neutrons in 18N and 20F leads to a major difference between the elastic form factors of these exotic nuclei and their stable isotopes 14N and 19F. The reaction c
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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 t
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This study dedicates to provide an information of shell model calculations, limited to fp-shell with an accuracy and applicability. The estimations depend on the evaluation of Hamiltoian’s eigenvalues, that’s compatible with positive parity of energy levels up to (10MeV) for most isotopes of Ca, and the Hamiltonian eigenvectors transition strength probability and inelastic electron-nucleus scattering. The Hamiltonian is effective in the regions where we have experimented. The known experimental data of the same were confirmed and proposed a new nuclear level for others.
The calculations are done with the help of OXBASH code. The results show good agreement with experimental energy states
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The ground state proton, neutron, and matter density distributions and corresponding root-mean-square radii (rms) of the unstable neutron-rich
22C exotic nucleus are investigated by two-frequency shell model (TFSM) approach. The single-particle wave functions of harmonic-oscillator (HO)
potential are used with two oscillator parameters bcore and bhalo. According to this model, the core nucleons of 20C are assumed to move in the model
space of spsdpf. Shell model calculations are performed with (0+2)hw truncations using Warburton-Brown psd-shell (WBP) interaction. The outer (halo) two neutrons in 22C are assumed to move in HASP (H. Hasper) model space (2s1/2, 1d3/2, 2p3/2, and 1f7/2 orbits) using the HASP interaction. The halo st
The elastic magnetic electron scattering form factors and the magnetic dipole moments have been studied for the ground state of 19C (halo) (JπT= 1/2+ 7/2) nucleus carried out using psd-shell Millener-Kurath (PSDMK) interactions. The single-particle wave functions of harmonic-oscillator (HO) potential are used with two different oscillator parameters bcore and bhalo. According to this interaction, the core nucleons of 18C nucleus are assumed to move in the model space of spd. The outer halo (1-neutron) in 19C is assumed to move in the pure 2s1/2 orbit. The elastic magnetic electron scattering of the stable 13C and exotic 19C nuclei are investigated through Plane Wave Born Approximation (PWBA). It is found that the difference between the
... Show MoreThe elastic magnetic electron scattering form factors and the magnetic dipole moments have been studied for the ground state of 19C (halo) (JπT= 1/2+ 7/2) nucleus carried out using psd-shell Millener-Kurath (PSDMK) interactions. The single-particle wave functions of harmonic-oscillator (HO) potential are used with two different oscillator parameters bcore and bhalo. According to this interaction, the core nucleons of 18C nucleus are assumed to move in the model space of spd. The outer halo (1-neutron) in 19C is assumed to move in the pure 2s1/2 orbit. The elastic magnetic electron scattering of the stable 13C and exotic 19C nuclei are investigated through Plane Wave Born Approximation (PWBA). It is found that the difference between the
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