Shell-model calculations on negative-parity levels in A = 35, 37 and 39 nuclei

1970 ◽  
Vol 141 (3) ◽  
pp. 481-496 ◽  
Author(s):  
S. Maripuu ◽  
G.A. Hokken
1984 ◽  
Vol 37 (1) ◽  
pp. 17 ◽  
Author(s):  
FC Barker

On the basis of a weak-coupling model, adjustments are made to the interactions used in the full shell model calculations of Millener in order to fit the experimental energies of the low-lying negativeparity levels of 16N and of the low-lying positive-parity levels of 180 and 190 . The predicted energies of the low-lying negative-parity levels of 17N then agree better with experiment, while those for 18N lead to suggested spin assignments for the observed levels.


2021 ◽  
Vol 66 (4) ◽  
pp. 293
Author(s):  
A.A. Al-Sammarraie ◽  
F.A. Ahmed ◽  
A.A. Okhunov

The negative-parity states of 24Mg nucleus are investigated within the shell model. We are based on the calculations of energy levels, total squared form factors, and transition probability using the p-sd-pf (PSDPF) Hamiltonian in a large model space (0 + 1) hW. The comparison between the experimental and theoretical states showed a good agreement within a truncated model space. The PSDPF-based calculations successfully reproduced the data on the total squared form factors and transition probabilities of the negative-parity states in 24Mg nucleus. These quantities depend on the one-body density matrix elements that are obtained from the PSDPF Hamiltonian. The wave functions of radial one-particle matrix elements calculated with the harmonic-oscillator potential are suitable to predict experimental data by changing the center-of-mass corrections.


2010 ◽  
Vol 19 (08n09) ◽  
pp. 1754-1762 ◽  
Author(s):  
YING-CHUN YANG ◽  
YANG SUN ◽  
T. TRIVEDI ◽  
R. PALIT ◽  
J. A. SHEIKH

A study of recently-measured high spin states of 75 Kr is carried out by using the Projected Shell Model. Calculations are performed up to spin I = 33/2 for the positive parity band and I = 27/2 for the negative parity band. Irregularities found in moment of inertia and in the deduced transition quadrupole moments Q t of the two bands are discussed in terms of the alignment of g 9/2 protons. Our study provides an insight into the shape evolution of the well-deformed nucleus 75 kr .


2017 ◽  
Vol 26 (06) ◽  
pp. 1750041 ◽  
Author(s):  
Dhanvir Singh ◽  
Arun Bharti ◽  
Amit Kumar ◽  
Suram Singh ◽  
G. H. Bhat ◽  
...  

The projected shell model (PSM) with the deformed single-particle states, generated by the standard Nilsson potential, is applied to study the negative-parity high spin states of [Formula: see text] nuclei. The nuclear structure quantities like band structure and back-bending in moment of inertia have been calculated with PSM method and are compared with the available experimental data. In addition, the reduced transition probabilities, i.e., B[Formula: see text] and B[Formula: see text], are also obtained for the yrast band of these isotopes for the first time by using PSM wave function. A multi-quasiparticle structure has been predicted for [Formula: see text] isotopes by the present PSM calculations.


1972 ◽  
Vol 50 (20) ◽  
pp. 2428-2443 ◽  
Author(s):  
D. W. O. Rogers ◽  
R. P. Beukens ◽  
W. T. Diamond

Using the 15N(α,γ)19F reaction, the properties of 6 levels between 5.3 and 6.2 MeV in 19F have been studied. In conjunction with previously reported restrictions on spins for these levels, measurements of branching ratios, radiative widths, and angular distributions have been used to make the following spin–parity assignments; 5618 keV, 3/2−; 5938 keV, 1/2+; 6070 keV, 7/2+; 6088 keV, 3/2−; 6160 keV, 7/2−. The properties of these levels and that at 5336 keV have been compared in detail to the various shell model calculations done for 19F. The properties of the third Jπ = 7/2+ level at 6.07 MeV can be used to clear up some of the confusion caused by the first two Jπ = 7/2+ levels in 19F and the properties of the Jπ = 3/2− levels confirm the fact that the weak coupling model does not explain the negative parity states outside the K = 1/2− band.


2010 ◽  
Vol 25 (21n23) ◽  
pp. 1972-1975 ◽  
Author(s):  
K. TAJIRI ◽  
K. KURA ◽  
M. KAZATO ◽  
M. SUGA ◽  
A. TAKASHIMA ◽  
...  

The level structures of 28 Mg and 29 Mg have been investigated by the β-decay of spin-polarized28 Na and 29 Na at ISAC, TRIUMF. The detailed β-γ and γ-γ coincidence measurements were performed. New γ rays and β transitions were observed both in 28 Mg and 29 Mg . We have succeeded in assigning spins and parities of many levels in 28 Mg and 29 Mg . Comparison with shell model calculations using USD Hamiltonian suggest that the structure of 28 Mg and 29 Mg are well explained in the sd-shell configurations, except for two levels at 1.095 and 1.430 MeV in 29 Mg . This suggests negative parity assignments for these levels. The evolution of sd-pf shell is discussed.


Nukleonika ◽  
2019 ◽  
Vol 64 (4) ◽  
pp. 113-116
Author(s):  
Wu Yi-Heng ◽  
Yang Dong ◽  
Ma Ke-Yan ◽  
Luo Peng-Wei

Abstract Shell model calculations have been carried out for 90Nb nucleus with the model space in which the valence protons occupy the f5/2, p3/2, p1/2, and g9/2 orbitals and the valence neutrons occupy the p1/2, g9/2, d5/2, and g7/2 orbitals. According to the calculated results, the negative parity is from the contribution of the proton of the f5/2, p3/2, and p1/2 orbits. The moderate spin states of 90Nb are mainly due to the excitation of protons from the f5/2 and p3/2 orbits to the p1/2 and g9/2 orbits across the Z = 38 subshell closure, and the high spin states arise from the excitation of a single neutron from the g9/2 orbit into the d5/2 orbit across the N = 50 shell closure.


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