Possible very anharmonic one- and two-phonon γ-vibrational bands in 103Mo

High-spin levels of [Formula: see text]Mo have been reinvestigated by analyzing the high statistics [Formula: see text]-[Formula: see text]-[Formula: see text] and [Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text] coincidence data from the spontaneous fission of [Formula: see text]Cf taken with the Gammasphere detector array. Two bands and 30 new transitions have been identified. A potential energy surface calculation has been performed. The calculation confirmed the 3/2[Formula: see text][411] configuration of the ground state band and 5/2[Formula: see text][532] for the 346[Formula: see text]keV excited band, as assigned in the previous work. The two newly established bands were proposed to be one- and two-phonon [Formula: see text] vibrational bands coupling to the 5/2[Formula: see text][532] Nilsson orbital, respectively. Triaxial projected shell model calculations have been applied to explain the level structure and are found in good agreement with experimental data.

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Reinvestigation of two-phonon γ-vibrational band in neutron-rich 114Pd

International Journal of Modern Physics E ◽

10.1142/s0218301316500646 ◽

2016 ◽

Vol 25 (09) ◽

pp. 1650064 ◽

Cited By ~ 2

Author(s):

Y. Huang ◽

S. J. Zhu ◽

J. H. Hamilton ◽

A. V. Ramayya ◽

E. H. Wang ◽

...

Keyword(s):

Experimental Data ◽

Shell Model ◽

Spontaneous Fission ◽

Level Structure ◽

Vibrational Band ◽

Projected Shell Model ◽

Previous Suggestion ◽

Model Calculations ◽

Good Agreement

The level structure in neutron-rich [Formula: see text]Pd nucleus has been reinvestigated by measuring prompt [Formula: see text] rays emitted in the spontaneous fission of [Formula: see text]Cf. A two-phonon [Formula: see text]-vibrational band built on the 1639.3[Formula: see text]keV level is observed, which confirms the previous suggestion from a [Formula: see text]-decay experiment. Systematical comparison supports the assignment for a two-phonon [Formula: see text]-vibrational band in [Formula: see text]Pd. Triaxial projected shell model calculations for the multi-phonon [Formula: see text] bands of [Formula: see text]Pd are in good agreement with the experimental data.

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New levels in spherical 96Y

International Journal of Modern Physics E ◽

10.1142/s0218301318500519 ◽

2018 ◽

Vol 27 (06) ◽

pp. 1850051

Author(s):

E. H. Wang ◽

J. H. Hamilton ◽

A. V. Ramayya ◽

R. Han ◽

C. J. Zachary ◽

...

Keyword(s):

Experimental Data ◽

Shell Model ◽

Large Deformation ◽

Ground State ◽

Spontaneous Fission ◽

Detector Array ◽

Model Calculations ◽

Coincidence Data ◽

Excited Band ◽

Good Agreement

New transitions in neutron rich [Formula: see text]Y have been identified by analyzing the high statistics [Formula: see text]-[Formula: see text]-[Formula: see text] and [Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text] coincidence data from the spontaneous fission of [Formula: see text]Cf at the Gammasphere detector array. Shell model calculations were performed and are found in good agreement with experimental data. The ground state is nearly spherical but a new excited band has large deformation.

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NEW STRUCTURES IN 178HF AND COULOMB EXCITATION OF ISOMERS

International Journal of Modern Physics E ◽

10.1142/s0218301311017879 ◽

2011 ◽

Vol 20 (02) ◽

pp. 474-481 ◽

Cited By ~ 3

Author(s):

A.B. HAYES ◽

D. CLINE ◽

C. Y. WU ◽

A.M. HURST ◽

M.P. CARPENTER ◽

...

Keyword(s):

Angular Momentum ◽

Ground State ◽

Coulomb Excitation ◽

National Laboratory ◽

Argonne National Laboratory ◽

Particle Detector ◽

Ground State Band ◽

Rotational Bands ◽

Coincidence Data ◽

State Band

A 985 MeV 178 Hf beam was Coulomb excited by a 208 Pb target at the ATLAS accelerator of Argonne National Laboratory. Gammasphere and the CHICO particle detector recorded particle-γ coincidence data. The aim was to populate and determine the mechanism of previously observed Coulomb excitation of the Kπ = 6+ (t1/2 = 77 ns ), 8- (4 s ) and 16+ (31 y ) isomer bands. New rotational bands were identified including an aligned band which appears to mix with the ground-state band (GSB) and the γ-vibrational band above ~ 12 ħ of angular momentum. Newly observed γ-decay transitions into the three isomer bands may elucidate the K-mixing which allows Coulomb excitation of these isomer bands, but direct decays from the GSB into the 16+ isomer band have not yet been confirmed.

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g-factors of some excited states in 49,50Cr

HNPS Proceedings ◽

10.12681/hnps.2388 ◽

2019 ◽

Vol 3 ◽

pp. 205

Author(s):

A. A. Pakou ◽

J. Billowes ◽

A. W. Mountford ◽

C. Tenreiro ◽

D. D. Warner

Keyword(s):

Magnetic Field ◽

Excited States ◽

Ground State ◽

Experimental Error ◽

Magnetic Moments ◽

Transient Field ◽

Ground State Band ◽

Model Calculations ◽

State Band ◽

G Factors

Magnetic moments of the first excited states in 50Cr and of the 7/2" and 19/2' states in 49Cr, have been measured by the transient field technique. The states were excited by the inverse reaction 40Ca + 12C and the recoil nuclei traversed a thick gadolinium foil. The observed rotations, of the 2+, 4+, 6+, 8+ states of the ground-state band in 50Cr, were found into the experimental error to be the same, suggesting similar g-factors for these states and thus supporting a high collectivity for the ground-state band, g-factors of the 7/2' and 19/2 states in 49Cr, were deduced by adopting both an overall parametrization of the transient magnetic field in Gd and by comparing the 49Cr rotations with rotations of states with known magnetic moments, as the 2+ ones of 50Cr and of 46Ti which was also populated in the same reaction. Both methods gave similar results and the g-factors adopted for the 19/2" and 7/2" states were + 0.78(17) and +0.35(7) respectively. These results are discussed in terms of cranked shell model calculations and are found to support a proton alignment in the f7/2 shell.

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Calculation of Nuclear Properties for 56–62Fe Isotopes in the Model Space (HO) Using NuShellX@MSU Code

Ukrainian Journal of Physics ◽

10.15407/ujpe66.8.643 ◽

2021 ◽

Vol 66 (8) ◽

pp. 643

Author(s):

F.H. Obeed

Keyword(s):

Transition Probability ◽

Energy Levels ◽

Model Space ◽

Nuclear Shell Model ◽

Quadrupole Transition ◽

Ground State Band ◽

Inertia Moment ◽

State Band ◽

Nuclear Shell ◽

Good Agreement

The nuclear shell model has been applied to calculate the yrast energy levels, quadrupole transition probability (BE2), deformation parameter B2, rotational energy (hw), and inertia moment (20/h2) for the ground state band. The NuShellX@MSU code has been used to determine the nuclear properties of 56−62Fe isotopes, by using the harmonic oscillator (HO) model space for P (1f7/2), N (2p3/2), N (1f5/2), and N (2p1/2) orbits and (HO) interaction. The results are in good agreement with the available experimental data on the above nuclear properties and all nuclei under study. In addition, the back bending phenomenon has been explained by the calculations, and it has been very clear in 58,60,62Fe nuclei. It has also been confirmed and determined the most spins and parities of energy levels. In these calculations, new values have been theoretically determined for the most nuclear properties which were previously experimentally unknown.

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Study of the Q.Q interaction

International Journal of Modern Physics E ◽

10.1142/s0218301318500568 ◽

2018 ◽

Vol 27 (07) ◽

pp. 1850056

Author(s):

Arun Kingan ◽

Xiaofei Yu ◽

Larry Zamick

Keyword(s):

Shell Model ◽

Quadrupole Interaction ◽

Single Particle ◽

Ground State ◽

Ground State Band ◽

Rotational Model ◽

Model Calculations ◽

State Band

We perform shell model calculations using a quadrupole–quadrupole interaction (Q.Q). We show results in single j shell spaces and the full S-D shell. We show that one gets useful results with Q.Q in both spaces. We emphasize the importance of the choice of single particle energies in order to obtain the results of Elliott using a Q.Q interaction without the momentum terms. We show a [Formula: see text] spectrum for a ground state band but with [Formula: see text]’s different from the rotational model. We also show results such as [Formula: see text] and [Formula: see text] excited “spin bands”. (The latter can also be expressed as a [Formula: see text] band). We find spectra starting with [Formula: see text] which have both even [Formula: see text] and odd [Formula: see text] members.

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