scholarly journals New levels in spherical 96Y

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.

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

2016 ◽  
Vol 25 (09) ◽  
pp. 1650064 ◽  
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.

Schalenmodellrechnungen beim Kern O18 mit geschwindigkeitsabhängigen Zwei-Teilchen-Potentialen

1967 ◽  
Vol 22 (4) ◽  
pp. 415-421
Author(s):  
Hans Grote
Keyword(s):  
Experimental Data ◽  
Harmonic Oscillator ◽  
Shell Model ◽  
Interaction Potential ◽  
Ground State ◽  
Wave Functions ◽  
Absolute Position ◽  
Model Calculations ◽  
The Core ◽  
Free Parameters

The energies of the low lying levels and the absolute position of the ground state of the nucleus O18 are calculated using five velocity-dependent potentials. The calculation is based on the shell model with two outer neutrons in the potential of the Ο16 core. The interaction potential as well as the core potential are fitted to experimental data, leaving no free parameters in the final result.The wave functions of the harmonic oscillator are used in each case of the five velocity-dependent potentials. An additional computation is carried out using one of these potentials and taking into account the perturbation of the wave functions. It turns out that, for satisfactory application of the velocity-dependent potentials in shell model calculations, this perturbation should be considered.

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

2017 ◽  
Vol 26 (05) ◽  
pp. 1750030 ◽  
Author(s):  
H. Fryman-Sinkhorn ◽  
E. H. Wang ◽  
C. J. Zachary ◽  
J. H. Hamilton ◽  
A. V. Ramayya ◽  
...  
Keyword(s):  
Level Structure ◽  
Ground State Band ◽  
Projected Shell Model ◽  
Model Calculations ◽  
Coincidence Data ◽  
Excited Band ◽  
Vibrational Bands ◽  
State Band ◽  
Good Agreement ◽  
Surface Calculation

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.

Study of 18O States by the 17O(d,p)18O Reaction

1975 ◽  
Vol 53 (9) ◽  
pp. 882-890 ◽  
Author(s):  
D. Drain ◽  
B. Chambon ◽  
J. L. Vidal ◽  
A. Dauchy ◽  
H. Beaumevieille
Keyword(s):  
Experimental Data ◽  
Shell Model ◽  
Cross Sections ◽  
Differential Cross ◽  
Ground State ◽  
Differential Cross Sections ◽  
Model Calculations ◽  
Absolute Differential ◽  
Spectroscopic Factors

The 17O(d,p)18O reaction was studied at Ed = 3.6 and 4.0 MeV. Absolute differential cross sections were measured for the ground state and the 1.98, 3.55, 3.63, 3.91, 4.45, 5.09, 5.25, and 5.37 MeV states in 18O. The experimental data are analyzed using the DWBA and Hauser–Feshbach theoreies and spectroscopic factors are deduced. These results are compared to previous data and shell model calculations. The correspondence between the above states and their analogue states in 18F is discussed.

scholarly journals THE METHOD OF INCREMENTS — A WAVEFUNCTION-BASED AB-INITIO CORRELATION METHOD FOR SOLIDS

2007 ◽  
Vol 21 (13n14) ◽  
pp. 2204-2214 ◽  
Author(s):  
BEATE PAULUS
Keyword(s):  
Experimental Data ◽  
Ab Initio ◽  
Ground State ◽  
Infinite System ◽  
Correlation Energy ◽  
Correlation Method ◽  
Many Body ◽  
Hartree Fock ◽  
The Many ◽  
Good Agreement

The method of increments is a wavefunction-based ab initio correlation method for solids, which explicitly calculates the many-body wavefunction of the system. After a Hartree-Fock treatment of the infinite system the correlation energy of the solid is expanded in terms of localised orbitals or of a group of localised orbitals. The method of increments has been applied to a great variety of materials with a band gap, but in this paper the extension to metals is described. The application to solid mercury is presented, where we achieve very good agreement of the calculated ground-state properties with the experimental data.

scholarly journals Study of sub-barrier fusion of 36S+50Ti,51V systems

2019 ◽  
Vol 223 ◽  
pp. 01013
Author(s):  
Giulia Colucci ◽  
Giovanna Montagnoli ◽  
Alberto M. Stefanini ◽  
Kouichi Hagino ◽  
Antonio Caciolli ◽  
...  
Keyword(s):  
Experimental Data ◽  
Comparative Study ◽  
Excitation Function ◽  
Ground State ◽  
Weak Coupling ◽  
Coupling Scheme ◽  
Excitation Functions ◽  
Coupled Channels ◽  
Barrier Distribution ◽  
Good Agreement

A detailed comparative study of the sub-barrier fusion of the two near-by systems 36S+50Ti,51V was performed at the National Laboratories of Legnaro (INFN). Aim of the experiment was the investigation of possible effects of the non-zero spin of the ground state of the 51V nucleus on the sub-barrier excitation function, and in particular on the shape of the barrier distribution. The results sh w that the two measured excitation functions are very similar down to the level of 20 - 30 μb. The same is observed for the two barrier distributions. Coupled-channels calculations have been performed and are in good agreement with the experimental data. This result indicates that the low-lying levels in 51V can be interpreted in the weak-coupling scheme, that is, 51V(I) = 50Ti(2+)⊗ p(1 f7/2).

scholarly journals A Search for an Excited Kp=0+ Rotational Band in 24Mg

1976 ◽  
Vol 29 (3) ◽  
pp. 139 ◽  
Author(s):  
D Branford ◽  
LE Carlson ◽  
FCP Huang ◽  
N Gardner ◽  
TR Ophel ◽  
...  
Keyword(s):  
Shell Model ◽  
Quadrupole Moment ◽  
Rotational Band ◽  
Doppler Shift ◽  
Transition Rates ◽  
Model Calculations ◽  
Doppler Shift Attenuation ◽  
Doppler Shift Attenuation Method ◽  
Absolute Transition ◽  
Good Agreement

A search is described for an excited Kn = 0+ rotational band based on the 6� 44 MeV level of 24Mg. Mean nuclear lifetimes have been measured by the Doppler shift attenuation method using the 12C('60,a)24Mg reaction and the results are 't'm = 66�29, 28�7 and 13�3 fs for levels at 6'44, 8�65 and 10� 58 MeV respectively. The absolute transition rates found for the y decays from the 6�44 and 8�65 MeV levels are in good agreement with the results of shell model calculations if it is assumed that these levels are the 0+ and 2 + members respectively of the excited Kn = 0+ rotational band. Based on this assumption, a result Qoo = 0�48 �0�08b is obtained for the intraband quadrupole moment. From a study of the 23Na(p, y) reaction, it is established that the J = 4 levels at 12� 63 and 13�05 MeV do not decay by enhanced E2 transitions to the 8� 65 MeV level. This suggests that neither of these levels is the 4 + member of the excited Kn = 0+ rotational band. An assignment of J" = 4+ is made to one member of the doublet at 10�58 MeV.

Simulating Radio Element Release and Water-Rock Interactions During Dissolution of Borosilicate Glass

1997 ◽  
Vol 506 ◽  
Author(s):  
A V Chambers ◽  
T G Heath ◽  
C M Linklater ◽  
A M Thompson ◽  
R M Wiggin
Keyword(s):  
Experimental Data ◽  
Borosilicate Glass ◽  
Glass Surface ◽  
Major Elements ◽  
Reaction Products ◽  
Exchange Reactions ◽  
Model Calculations ◽  
Dissolution Behaviour ◽  
Uranium Plutonium ◽  
Good Agreement

ABSTRACTA model has been developed that can simulate in some detail the chemistry of the glass dissolution process. To test the performance of the model, calculations were carried out to predict the dissolution behaviour of a commercial borosilicate glass. The model could reproduce accurately the behaviour of major elements released from the glass, although in the case of silica, ‘sorption’ at the glass surface was required in order to achieve good agreement with experimental data. Secondary reaction products sepiolite, montmorillonite, analcime and goethite were predicted to form. Further calculations were carried out to simulate the release of radioelements (caesium, strontium, uranium, plutonium) from within the dissolving glass. The precipitation of insoluble solids was the only mechanism included in the model to retain the radioelements at the glass surface. For plutonium, there was good agreement between model predictions and available experimental data. For caesium and strontium, the model underestimated the amount of retention at the glass surface and additional retention mechanisms, such as coprecipitation or ion exchange reactions involving newly-formed clay-type minerals at the glass surface must be invoked to explain experimental observation.

The octupole deformation of 143Ba

2015 ◽  
Vol 24 (11) ◽  
pp. 1550081 ◽  
Author(s):  
Yong-Jing Chen ◽  
Yong-Shou Chen ◽  
Zao-Chun Gao ◽  
Ya Tu
Keyword(s):  
Experimental Data ◽  
Shell Model ◽  
Ground State ◽  
Wave Functions ◽  
Rotational Bands ◽  
Octupole Deformation ◽  
Quantum Numbers

Based on existence of the octupole deformation in the intrinsic states, the experimentally observed four rotational bands in [Formula: see text]Ba have been well reproduced by the reflection asymmetric shell model (RASM) calculations. Through the analysis of the calculated RASM wave functions, the intrinsic configuration of the observed rotational bands has been assigned as the octupole deformed neutron [Formula: see text] orbit, which is just located below the [Formula: see text] shell gap. The calculated results supported the ground state octupole deformation and the purity of the simplex quantum numbers [Formula: see text] in [Formula: see text]Ba. In addition, the calculated [Formula: see text] values are in agreement with experimental data, and further support the octupole deformation in [Formula: see text]Ba.

55 YEARS OF THE SHELL MODEL: A CHALLENGE TO NUCLEAR MANY-BODY THEORY

2005 ◽  
Vol 14 (06) ◽  
pp. 821-844 ◽  
Author(s):  
IGAL TALMI
Keyword(s):  
Shell Model ◽  
Wave Functions ◽  
Many Body ◽  
Apparent Absence ◽  
Model Calculations ◽  
Many Body Theory ◽  
Body Theory ◽  
Nuclear Many Body Theory ◽  
Closed Shells ◽  
Good Agreement

Shell model calculations of nuclear energies and wave functions of nucleons outside closed shells interacting by effective two-body forces yield good agreement with much experimental data. Many attempts have been made to calculate nuclear energies ab initio, by starting from some form of an interaction between free nucleons. Recent results of such calculations claim to obtain reasonable agreement with measured energies. These results, however, are obtained for wave functions which are very complicated. It is difficult to see how such wave functions are consistent with independent nucleon motion, the very essence of the shell model. In some of those calculations, 3-body interactions play a very important role. This is puzzling since nuclear energies are accurately obtained in shell model calculations by using only effective two-body interactions. In this paper, some examples of simple shell model calculations are reviewed. They exhibit good agreement with experiment and the apparent absence of the need for effective 3-body interactions.

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