DEGENERATING CLUSTERS IN AN UNBOUND REGION OF 12Be

2009 ◽  
Vol 24 (11) ◽  
pp. 2175-2182 ◽  
Author(s):  
MAKOTO ITO
Keyword(s):  
Excitation Energy ◽  
Single Particle ◽  
Cluster Model ◽  
Particle Decay ◽  
Decay Threshold

The generalized two-center cluster model (GTCM), which can treat various single particle configurations in general two center systems, is applied to the light neutron-rich system, 12 Be = α+α+4N. We discuss the change of the neutrons' configuration around two α-cores as a variation of an excitation energy. We found that the covalent, ionic and atomic configurations appear with a prominent degenerating feature above the α+8 He g.s. particle-decay threshold.

ASYMMETRIC CLUSTERS IN EVEN Be ISOTOPES

2010 ◽  
Vol 25 (21n23) ◽  
pp. 1862-1865
Author(s):  
MAKOTO ITO
Keyword(s):  
Excitation Energy ◽  
Single Particle ◽  
Cluster Model ◽  
Particle Decay ◽  
Decay Threshold

The generalized two-center cluster model (GTCM), which can treat various single particle configurations in general two center systems, is applied to light neutron-rich systems, Be isotopes (α+α+ X N). We discuss the change of the neutrons' configuration around two α-cores as a variation of an excitation energy. We show that the asymmetric clusters, which correspond to the atomic or ionic configurations, appear in the unbound region above the α particle-decay threshold systematically.

COVALENT, IONIC, AND ATOMIC STRUCTURES IN 12Be

2009 ◽  
Vol 24 (11n13) ◽  
pp. 1005-1008 ◽  
Author(s):  
MAKOTO ITO ◽  
NAOYUKI ITAGAKI
Keyword(s):  
Excitation Energy ◽  
Single Particle ◽  
Cluster Model ◽  
Energy Interval ◽  
Small Energy ◽  
Atomic Structures ◽  
Particle Decay ◽  
Decay Threshold

The generalized two-center cluster model (GTCM), which can treat various single particle configurations in general two center systems, is applied to the light neutron-rich system, 12 Be = α+α+4N. We discuss the change of the neutrons' configuration around two α-cores as a variation of an excitation energy. We show that the covalent, ionic and atomic configurations appear in the unbound region above the α+8 He g.s. particle-decay threshold, and they coexist within a quite small energy interval.

MASS AND LIFETIME MEASUREMENTS AT THE PRESENT ESR FACILITY

2009 ◽  
Vol 18 (02) ◽  
pp. 323-334 ◽  
Author(s):  
YURI A. LITVINOV
Keyword(s):  
Mass Spectrometry ◽  
Single Particle ◽  
Experimental Methods ◽  
Lifetime Measurements ◽  
Time Resolved ◽  
Particle Decay ◽  
Decay Properties ◽  
Decay Spectroscopy ◽  
Beta Decays ◽  
Charged Ions

Mass and lifetime measurements of stored exotic nuclei is one of the successful experimental programs at the FRS-ESR facility of GSI, Darmstadt. Two experimental techniques, namely Isochronous and time-resolved Schottky mass spectrometry have been developed. Nuclides in a very broad range of half-lives starting from stable down to only a few ten microseconds can be addressed. Single stored ions can be measured which makes these techniques highly efficient. More than 1100 atomic masses have been measured meanwhile. Half-life measurements are performed with bare and few-electron ions. Decay properties of such highly-charged ions can be dramatically different from the ones known in neutral atoms. Single-particle decay spectroscopy has been developed for investigations of two-body beta decays. A brief description of the experimental methods and recent results will be presented. Future experiments at the present facility and the perspectives with the new NuSTAR/ILIMA project at FAIR will be outlined.

DECAY PROPERTIES OF SHORT LIVED RESONANCES OF LIGHT NUCLEI IN MANY-PARTICLE NUCLEAR REACTIONS

2010 ◽  
Vol 19 (05n06) ◽  
pp. 1220-1226 ◽  
Author(s):  
YU. N. PAVLENKO ◽  
V. N. DOBRIKOV ◽  
N. L. DOROSHKO ◽  
O. K. GORPINICH ◽  
T. A. KORZINA ◽  
...  
Keyword(s):  
Excitation Energy ◽  
Nuclear Reactions ◽  
Coulomb Field ◽  
Light Nuclei ◽  
Final State ◽  
Resonance Parameters ◽  
Decay Properties ◽  
Unbound States ◽  
Decay Threshold

The decay properties of nuclear unbound states formed in the reactions with three particles in the final state are reviewed. The modification of resonance parameters observed in these reactions and caused by the influence of the Coulomb field of accompanied particles is analyzed for the resonances with excitation energy near and far from the decay threshold.

ASYMMETRIC CLUSTERS IN 14Be

2011 ◽  
Vol 20 (04) ◽  
pp. 870-873
Author(s):  
MAKOTO ITO
Keyword(s):  
Excited States ◽  
Single Particle ◽  
Level Scheme ◽  
Cluster Model ◽  
Cluster Configuration

The generalized two-center cluster model (GTCM), which can treat various single particle configurations in general two-center systems, is applied to 14 Be =α+α+6N. We mainly investigate an appearance of asymmetric cluster structures, 6 He +8 He , in the excited states of 14 Be . The level scheme in 14 Be is discussed in a comparison with that in 10 Be . The relation between 14 Be and 10 Be can be understood from the viewpoint of the particle-hole symmetry in the x He +y He cluster configuration.

ELASTIC AND INELASTIC PROTON MULTIPLE SCATTERING ON 12C AND 16O NUCLEI

1991 ◽  
Vol 06 (09) ◽  
pp. 775-780 ◽  
Author(s):  
YU. A. BEREZHNOY ◽  
V.P. MIKHAILYUK ◽  
V.V. PILIPENKO
Keyword(s):  
Experimental Data ◽  
Inelastic Scattering ◽  
Multiple Scattering ◽  
Single Particle ◽  
Scattering Theory ◽  
Cluster Model ◽  
Diffraction Scattering ◽  
Multiple Diffraction ◽  
Nucleon Density ◽  
Mev Protons

The elastic and inelastic scattering polarization observables of the 800 MeV protons on 12C and 16O nuclei are calculated on the basis of the multiple diffraction scattering theory. It was shown that the results of the calculations for elastic p-12C and p-16O scattering by the α-cluster model with dispersion are in a better agreement with the experimental data than those with the single-particle nucleon density.

NUCLEAR LEVEL DENSITY OF HEAVY NUCLEI Z≥90 THROUGH SEMICLASSICAL METHOD

2014 ◽  
Vol 29 (03) ◽  
pp. 1450017 ◽  
Author(s):  
M. R. PAHLAVANI ◽  
S. A. ALAVI ◽  
E. FARHADI
Keyword(s):  
Excitation Energy ◽  
Single Particle ◽  
Level Density ◽  
Energy Shift ◽  
Density Parameter ◽  
Heavy Nuclei ◽  
Nuclear Level Density ◽  
Nuclear Level ◽  
Single Particle Level ◽  
Particle Level

The nuclear level density parameters of back shift Fermi gas model, including single-particle level density parameter a and excitation energy shift E1, for some heavy nuclei have been calculated in the framework of semiclassical approach. The single-particle level density have been obtained for mean-field Woods–Saxon potential. By using the obtained values of single-particle level density parameter and excitation energy shift, the spin cut-off factor has been calculated at the neutron binding energy.

scholarly journals A study of shell model neutron states in 207,209Pb using the generalized Woods–Saxon plus spin-orbit potential

2016 ◽  
Vol 25 (08) ◽  
pp. 1650055 ◽  
Author(s):  
J. A. Liendo ◽  
E. Castro ◽  
R. Gómez ◽  
D. D. Caussyn
Keyword(s):  
Angular Momentum ◽  
Excitation Energy ◽  
Single Particle ◽  
Binding Energies ◽  
Nuclear Surface ◽  
Spin Orbit ◽  
Coupling Term ◽  
Angular Momentum Quantum Number ◽  
Orbit Potential ◽  
Number Formula

The experimental binding energies of single-particle and single-hole neutron states belonging to neutron shells that extend from [Formula: see text] = 126–184 and 82–126, respectively, have been reproduced by solving the Schrödinger equation with a potential that has two components: the generalized Woods–Saxon (GWS) potential and the spin-orbit (SO) coupling term. The GWS potential contains the traditional WS potential plus a term (SU) whose intensity reaches a maximum in the nuclear surface. Our results indicate the existence of an explicit relationship between the strength of the SU potential and the orbital angular momentum quantum number [Formula: see text] of the state. This dependence has been used to make reasonable predictions for the excitation energy centroids of states located inside and outside the neutron shells investigated. Comparisons are made with results reported in previous investigations.

scholarly journals Analogues of Excited States in 91Zr

1969 ◽  
Vol 22 (4) ◽  
pp. 541 ◽  
Author(s):  
GA Jones ◽  
GC Morrison ◽  
RB Taylor
Keyword(s):  
Excitation Energy ◽  
Excited States ◽  
Single Particle ◽  
Ground State ◽  
Level Structure ◽  
Positive Parity

The level structure in 91Zr has been investigated by Cohen and Chubinsky (1963) with the 90Zr (d, p)91Zr reaction. They noted some 14 levels up to an excitation energy of 3�9 MeV. All these states were found to have positive parity and their structure is fairly well understood in terms of coupling a single-particle neutron to the ground state and the first two excited states of 90Zr (Ramavataram 1964). A study of the isobaric analogues of the 9lZr states with the 90Zr(p, pO)90Zr reaction was carried out by Moore (1964).

Intensity anomaly in the (d,pγ) reaction

1970 ◽  
Vol 48 (6) ◽  
pp. 687-708 ◽  
Author(s):  
G. A. Bartholomew ◽  
I. Bergqvist ◽  
E. D. Earle ◽  
A. J. Ferguson
Keyword(s):  
Excitation Energy ◽  
Gamma Rays ◽  
Single Particle ◽  
Gamma Ray ◽  
Strength Function ◽  
Neutron Separation Energy ◽  
Separation Energy ◽  
Excitation Energies

The spectra of gamma rays detected in coincidence with protons from the (d,pγ) reaction in elements [Formula: see text] and [Formula: see text] have been measured in gross structure with a NaI detector. The region of excitation energies covered in the product nuclei was from 0.8 MeV to about the neutron separation energy, typically 7 MeV. The gamma-ray anomalous bump at about 5.5 MeV was found from regions near the separation energy with an intensity comparable to that previously observed in (n,γ) reactions. By gating techniques the decay of many contiguous intervals of excitation energy, populated in the reaction, was studied. From the results, a strength function for gamma rays between 0.8 and 7 MeV approximately was extracted for Au, where the bump is prominent, and for Ta where the bump is essentially absent. In the particular case of 206Pb(d,pγ)207Pb, the gamma-ray spectra are interpreted in terms of the decay of known single particle states. An interpretation of the intensity anomaly in terms of doorway states is discussed.

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