THE Sr88(d, p)Sr89 REACTION

1964 ◽  
Vol 42 (2) ◽  
pp. 321-328 ◽  
Author(s):  
R. L. Preston ◽  
M. B. Sampson ◽  
H. J. Martin
Keyword(s):  
Shell Model ◽  
Ground State ◽  
Energy Levels ◽  
Angular Distributions ◽  
Q Value ◽  
Excitation Energies ◽  
Analogous Data ◽  
State Spin

Thirteen energy levels in Sr89 were excited by the Sr88(d, p)Sr89 reaction. The excitation energies of the levels are 0, 1.04, 2.00, 2.44, 2.67, 3.18, 3.45, 3.74, 4.10, 4.44, 4.60, 4.97, and 5.38 Mev. The ground-state Q-value is 4.15 ± 0.04 Mev. Angular distributions were measured for protons leaving Sr89 in the first three levels and for the 3.74-Mev state. Spin assignments were made using the shell model and the DWBA stripping theory. The assignments are 2d5/2 for the ground state, 3s1/2 for the 1.04-Mev state, 2d3/2 for the 2.00-Mev state, and [Formula: see text] for the 3.74-Mev state. The results are compared with analogous data on Zr91 levels.

Energy Levels of 50Ca Nucleus as a Function of the Classical Coupling Angle within MSDI

2021 ◽  
Vol 19 (5) ◽  
pp. 61-67
Author(s):  
Ali Khalaf Hasan ◽  
Dalal Naji Hameed
Keyword(s):  
Experimental Data ◽  
Angular Momentum ◽  
Shell Model ◽  
Energy Levels ◽  
Model Space ◽  
Closed Shell ◽  
Excitation Energies ◽  
Modified Surface ◽  
Coupling Angle ◽  
Surface Delta Interaction

In the construction of this kind of shell model, we take the residual interaction to be modified surface delta interaction MSDI. We have studied the excitation energies of the 50Ca a nucleus, which contain two neutrons outside closed shell of the 48Ca. Neutrons are in the model space pfpg. The energy levels and angular momentum of all possible cases were investigated. Thereby, we have effectively utilized a theoretical process to find link among the traditional coupling angle and energy levels at different orbital within neutron - neutron interaction. We observe the energy stages appear to follow two overall functions which depend on the classical coupling angles but are unconstrained of angular momentum I. We find out that our results agree with the experimental data.

The 12 C(γ, 3α) reaction energy levels of 8 Be and 12 C

1955 ◽  
Vol 228 (1174) ◽  
pp. 376-396 ◽  
Keyword(s):  
Ground State ◽  
Energy Levels ◽  
Electric Quadrupole ◽  
Angular Distributions ◽  
Reaction Energy ◽  
Reaction Proceeds ◽  
Γ Ray ◽  
Relationship Of ◽  
The Relationship ◽  
Α Particles

The mechanism of the 12 C(γ, 3α) reaction, for γ-ray energies, E γ , up to about 40 MeV, has been determined from a study of over 2500 stars in nuclear emulsions. The study includes investigation of the angular distributions and correlations of the α-particles. The reaction is initiated mainly by electric-dipole and electric-quadrupole γ-ray interaction, the former being unexpectedly strong when E γ < 20 MeV. For E γ < 25 MeV the reaction proceeds mainly by transitions to the ground-state of 8 Be (spin J = 0), and to 2⋅95 ± 0⋅10 MeV ( J = 2) and 4⋅0 ± 0⋅1 MeV ( J = 2 or 4) levels of 8 Be. Transitions to levels near 6, 10 and 15 MeV (all J = 0, 2 or 4) become predominant when 25 MeV ≤ E γ <26 MeV. For E γ ≥ 26 MeV, most transitions lead to 16⋅8 ± 0⋅2 MeV ( J = 2) and 17⋅6 ± 0⋅2 MeV ( J = 2, possibly 0) levels, and possibly to a further 16⋅4 ± 0⋅2 MeV ( J = 0 or 2) level, levels which have not been detected in other reactions. The reaction mechanism is interpreted in terms of competing modes of decay of a compound nucleus, demonstrating the strong influence of the isotopic spins ( T ) of the levels of 12 C and 8 Be involved. For example, the 2 + levels of 12 C involved when 16 MeV ≤ E γ <20 MeV are (unexpectedly) found to have T = 1, and the 16⋅8 and 17⋅6 MeV levels of 8 Be are also found to have T = 1. The relationship of the 12 C (γ, 3α) reaction to other 12 C photodisintegration reactions (including some new reactions established during the present experiments) is discussed.

Shell model description of the 0+ and 0− excited states in sd shell nuclei

2018 ◽  
Vol 96 (7) ◽  
pp. 774-778 ◽  
Author(s):  
M. Bouhelal ◽  
N. Saidane ◽  
S. Belaid ◽  
F. Haas
Keyword(s):  
Shell Model ◽  
Excited States ◽  
Ground State ◽  
Model Description ◽  
Excitation Energies ◽  
Model Calculations ◽  
The Future

The purpose of this work is to describe, in light of shell model calculations using the PSDPF interaction, the particular states with J = 0 in sd shell nuclei. These states are difficult to observe. It is well known that the ground state in even–even nuclei has Jπ = 0+ and therefore we are interested in describing their first excited [Formula: see text] states. We have also studied the first and second excited 0− states in all sd nuclei. The experimental and theoretical excitation energies of these states were confronted. This study allowed us to make predictions of the existence of [Formula: see text] and (or) [Formula: see text] states in nuclei, which do not possess these states, or to have an idea of their excitation energies for possible experiments in the future.

TWO-HOLE TWO-PARTICLE LEVELS IN Pb208

1963 ◽  
Vol 41 (3) ◽  
pp. 478-483 ◽  
Author(s):  
William T. Pinkston ◽  
William W. True
Keyword(s):  
Wave Function ◽  
Shell Model ◽  
Ground State ◽  
Energy Levels ◽  
Closed Shell ◽  
Ground State Wave Function ◽  
Energy Matrix ◽  
State Wave

The energy levels of Pb208 arising from certain two-hole two-particle shell-model configurations have been predicted theoretically. It is concluded that only a few such levels are expected in Pb208 and all of them have energies greater than or about equal to 6 Mev. The closed-shell core was included in the J = 0+ energy matrix in order to get an estimate of the two-body correlations in the ground state. Only a few per cent of higher configurations is predicted for the ground-state wave function.

A study of levels in 147Nd using the (d,t) reaction

1977 ◽  
Vol 55 (19) ◽  
pp. 1687-1696 ◽  
Author(s):  
O. Straume ◽  
D. G. Burke
Keyword(s):  
Ground State ◽  
State Transition ◽  
Energy Levels ◽  
Striking Similarity ◽  
Angular Distributions ◽  
Reaction Products ◽  
Proton Group ◽  
Energy Proton ◽  
Photographic Emulsions ◽  
Peak Widths

The 148Nd(d,t)147Nd reaction has been studied using 12 MeV deuterons. The reaction products were analyzed with an Enge-type magnetic spectrograph and detected with photographic emulsions, giving peak widths (FWHM) of approximately 8 keV. The present results confirm previous indications that the highest energy proton group found in an early 146Nd(d,p) investigation does not correspond to the ground state transition, but to the level at an excitation energy of 50 keV. The (d,t) angular distributions were used to determine l-values for a number of transitions. A striking similarity is noted with the energy levels and spectroscopic strengths previously found in the isotones 149Sm and 151Gd. With the exception of the h11/2 state, it is possible to explain the observed strengths in terms of the spherical shell model, although there is fragmentation of the spherical states.

A Study of Levels in 149Nd using the (d, t) and (3He, α) Reactions

1973 ◽  
Vol 51 (4) ◽  
pp. 455-464 ◽  
Author(s):  
D. G. Burke ◽  
J. C. Waddington ◽  
D. E. Nelson ◽  
J. Buckley
Keyword(s):  
Cross Sections ◽  
Ground State ◽  
State Transition ◽  
Angular Distributions ◽  
Ground State Transition ◽  
Reaction Products ◽  
Q Value ◽  
Nilsson Model ◽  
Photographic Emulsions ◽  
Peak Widths

Triton spectra from the 150Nd(d, t)149Nd reaction have been measured at 15 angles using beams of 12 MeV deuterons. The 150Nd(3He, α)149Nd reaction was studied at four angles with 24 MeV 3He beams. In all cases the reaction products were analyzed with an Enge-type magnetic spectrograph and detected with photographic emulsions. The peak widths (FWHM) were approximately 8 keV for the (d, t) studies and 25 keV for the (3He, α) spectra. It is now evident that the highest energy triton group ascribed to the 150Nd(d, t)149Nd reaction in previous works does not correspond to the ground state transition. According to the current interpretation the ground state transition has a Q value of −1.122 ± 0.010 MeV. The (d, t) angular distributions and the ratios of (3He, α) and (d, t) cross sections at selected angles were used to determine l values for a number of the transitions. Three states in 149Nd at 481, 813, and 986 keV are definitely populated by l = 0 transitions and thus have Iπ = 1/2+. A strongly perturbed band consisting of a mixture of Nilsson states from the i13/2 shell has been found, with properties similar to the corresponding bands in the isotones 151Sm and 153Gd. The total observed intensity for each of the l values 0, 1, 2, and 6 cannot be explained by the extreme single-particle shell model but is consistent with that predicted by the Nilsson model. However, the splitting of the strength among the observed states cannot be explained by the basic Nilsson model.

Angular distributions from ( d, p ) and ( d, n ) nuclear reactions

1951 ◽  
Vol 208 (1095) ◽  
pp. 559-579 ◽  
Keyword(s):  
Excited States ◽  
Ground State ◽  
Nuclear Reactions ◽  
Energy Levels ◽  
Angular Distributions ◽  
Angular Momenta ◽  
First Excited State ◽  
Compound Nucleus Formation ◽  
Initial Nucleus

Experimental angular distributions from (d, p) and (d, n) nuclear reactions involve con­tributions from incident angular momenta much higher than is compatible with compound nucleus formation, and indicate that these reactions must proceed to a large extent by means of a stripping process. The angular distributions to be expected from a stripping process are calculated, and these are found to be very sensitive to the angular momenta which can be accepted by the initial nucleus, i.e. to the spins and parities of the energy levels involved. In any one case there is found excellent agreement between the experimental curve and just one of the possible theoretical curves, and if the spin and parity of the ground state of the initial nucleus is known, this allows of a determination of the spin and parity of the appropriate level of the final nucleus. In this way it is found, for example, that the ground state of 17 O has spin ⅝ or ⅜ and even parity, and that the first excited state of 17 O (0.88 MeV above ground) has spin ½ and even parity. Determinations are also made of the spins and parities of the ground states and several excited states of 13 C, 15 N and 28 Al. Families of theoretical curves for a variety of incident and outgoing energies are presented in order to facilitate further spin and parity determinations from future experimental results.

Energies of Some 25Al Levels from the 24Mg(p,γ)25Al Reaction and the Coulomb-Energy Differences of Analog Rotational Bands

1971 ◽  
Vol 49 (4) ◽  
pp. 402-406 ◽  
Author(s):  
F. Everling ◽  
G. L. Morgan ◽  
D. W. Miller ◽  
L. W. Seagondollar ◽  
P. W. Tillman Jr.
Keyword(s):  
Gamma Rays ◽  
Ground State ◽  
Mass Number ◽  
Resonance Energy ◽  
Coulomb Energy ◽  
Q Value ◽  
Ground State Band ◽  
Excitation Energies ◽  
Rotational Bands ◽  
State Band

Gamma rays from the 24Mg(p, γ)25Al reaction at the 1201 and 1485 keV resonances were measured with a 20 cm3 Ge(Li) detector. Excitation energies obtained for known levels in 25Al are (in keV): 1612.5 ± 0.5, 1789.6 ± 1.3, 3424.3 ± 0.6, and 3696.3 ± 1.1. By using the known 1201.4 ± 1.0 keV resonance energy, a more precise Q value of 2271.4 ± 1.2 keV is obtained, 16 keV lower than the previous value which had a 6 keV uncertainty.A brief discussion of the Coulomb-energy differences of 25Al and 25Mg analog rotational bands in relation to the 24Mg ground-state band is given and compared with the situation at mass number A = 21.

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