States in the N = 87 Nuclei 149Sm and 151Gd Populated by the (d, t) and (3He,α) Reactions

1975 ◽  
Vol 53 (12) ◽  
pp. 1182-1192 ◽  
Author(s):  
G. Løvhøiden ◽  
D. G. Burke
Keyword(s):  
Spherical Shell ◽  
Shell Model ◽  
High Spin ◽  
Cross Sections ◽  
Striking Feature ◽  
Angular Distributions ◽  
Spin States ◽  
Reaction Products ◽  
Photographic Emulsions

The (d, t) and (3He, α) reactions on targets of 150Sm and 152Gd have been studied using a magnetic spectrograph and photographic emulsions to analyze and detect the reaction products. The (3He, α) spectra were measured at two angles for each target using 24 MeV beams of 3He. The 150Sm(d, t)149Sm reaction was studied at 13 angles with 12 MeV deuterons. The 152Gd(d, t)151Gd spectra were recorded at 4 angles with 15 MeV deuterons. The l values for a number of low spin states were determined from the (d, t) angular distributions. The ratios of (3He, α) and (d, t) cross sections were used to obtain l values for several other states. It is possible to explain the observed strength in terms of the spherical shell model although there is fragmentation of the spherical states. One striking feature is the similarity in the structures of the two nuclei. In both 149Sm and 151Gd there are high spin i13/2 states at ~0.85 MeV and h11/2 states at ~1.25 MeV.

Odd Proton States in 165Tm, 167Tm, 169Tm, and 171Tm

1974 ◽  
Vol 52 (21) ◽  
pp. 2108-2126 ◽  
Author(s):  
H. C. Cheung ◽  
D. G. Burke ◽  
G. Løvhøiden
Keyword(s):  
Proton Transfer ◽  
Nuclear Structure ◽  
Cross Sections ◽  
Quadrupole Deformation ◽  
Angular Distributions ◽  
Coriolis Coupling ◽  
Reaction Products ◽  
Structure Factors ◽  
Nilsson Model ◽  
Photographic Emulsions

Proton states in the odd mass isotopes 165Tm, 167Tm, 169Tm, and 171Tm have been studied using (3He, d) and (α, t) reactions with 24 MeV 3He and 27 MeV 4He beams. The reaction products were analyzed with a magnetic spectrograph and detected with photographic emulsions, giving a resolution (FWHM) of 16–18 keV. The proton transfer l values were determined from (3He, d) angular distributions and from the ratios of (3He, d) and (α, t) cross sections. Nuclear structure factors, extracted using DWBA cross sections, were compared to those predicted by the Nilsson model with pairing corrections and Coriolis coupling included. Most of the previous assignments for low lying proton states have been confirmed, and several new ones were made. It is shown that the energy systematics of the intrinsic proton states cannot be attributed to variations in the quadrupole deformation, ε2, but can be explained by a small monotonic variation in the hexadecapole deformation, ε4.

A study of levels in 155Dy using the (d,t) and (3He,α) reactions

1976 ◽  
Vol 54 (12) ◽  
pp. 1258-1273 ◽  
Author(s):  
O. Straume ◽  
D. G. Burke ◽  
T. F. Thorsteinsen
Keyword(s):  
Nuclear Structure ◽  
Cross Sections ◽  
Negative Parity ◽  
Positive Parity ◽  
Angular Distributions ◽  
Coriolis Coupling ◽  
Reaction Products ◽  
Nilsson Model ◽  
Photographic Emulsions ◽  
Peak Widths

The (d,t) and (3He, α) reactions on a target of 156Dy have been used to study the nuclear structure of 155Dy. Beams of 15 MeV deuterons and 24 MeV 3He were obtained from the McMaster University FN tandem Van de Graaff accelerator. The reaction products were analyzed with an Enge-type magnetic spectrograph and detected in photographic emulsions. The (d,t) reaction was studied at 15 angles with typical peak widths (FWHM) of ~ 6 keV and (3He,α) exposures were made at 5 angles with peak widths of ~ 18 keV. The (d,t) angular distributions and ratios of the (3He,α) and (d,t) cross sections were used to determine l values for a number of transitions. It is found that the positive parity states can be described in terms of the Nilsson model when Coriolis coupling is included while for the negative parity states only the gross features are well-described this way.

Nuclear Reaction Studies of 151Sm

1973 ◽  
Vol 51 (18) ◽  
pp. 2000-2022 ◽  
Author(s):  
D. E. Nelson ◽  
D. G. Burke ◽  
J. C. Waddington ◽  
W. B. Cook
Keyword(s):  
Cross Sections ◽  
Coulomb Excitation ◽  
Negative Parity ◽  
Angular Distributions ◽  
Neutron Transfer ◽  
Reaction Products ◽  
Single Neutron ◽  
Nilsson Model ◽  
Nuclear Levels ◽  
Photographic Emulsions

Properties of nuclear levels in 151Sm have been studied by measuring angular distributions for the 152Sm(d,t)151Sm reaction and spectra at several angles for the 152Sm(3He,α)151Sm and 150Sm(d,p)151Sm reactions. The reaction products were analyzed with a magnetic spectrograph and detected with photographic emulsions. Transfer l values were deduced from the (d,t) angular distributions and from the ratios of (3He,α) and (d,t) cross sections. The (d,t), (d,p), and (3He,α) reactions on targets of 151Sm were also studied in order to learn more about the wave function of the 151Sm ground state. The low-lying positive parity levels can be described by the Nilsson model with Coriolis and ΔN = 2 interactions included. However, the properties of the low energy negative parity states could not be explained as easily. No mixture of Nilsson states was found which could simultaneously explain the single neutron transfer intensities and the Coulomb excitation probabilities from previous measurements.

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.

A Study of Levels in 153Gd Using the (d,t) and (3He,α) Reactions

1973 ◽  
Vol 51 (22) ◽  
pp. 2354-2368 ◽  
Author(s):  
G. Løvhøiden ◽  
D. G. Burke
Keyword(s):  
Cross Sections ◽  
Negative Parity ◽  
Positive Parity ◽  
Angular Distributions ◽  
Reaction Products ◽  
Ground State Band ◽  
Intensity Pattern ◽  
Nilsson Model ◽  
State Band ◽  
Photographic Emulsions

Triton spectra from the 154Gd(d,t)153Gd reaction have been measured at 15 angles using a beam of 15 MeV deuterons. The 154Gd(3He,α)153Gd reaction was studied at 4 angles with a 24 MeV 3He beam. The reaction products were analyzed with an Enge-type magnetic spectrograph and detected with photographic emulsions. The (d,t) angular distributions and ratios of the (3He,α) and (d,t) cross sections were used to determine l values for a number of transitions. Members of the strongly perturbed band consisting of a mixture of Nilsson states from the i13/2 shell have been populated. An attempt has been made to describe some of the positive parity states in terms of the Nilsson model with Coriolis and ΔN = 2 mixings included. As spin assignments are now available for a large number of positive parity levels, it is possible to see a better developed pattern for this mixing than was presented previously. Although the observed intensity pattern for the 3/2−[521] ground-state band agrees with expectations, the remaining negative parity states cannot be easily explained in terms of the basic Nilsson model.

scholarly journals High-spin states and lifetimes in S33 and shell-model interpretation in the sd−fp space

2017 ◽  
Vol 96 (2) ◽  
Author(s):  
S. Aydin ◽  
M. Ionescu-Bujor ◽  
G. Tz. Gavrilov ◽  
B. I. Dimitrov ◽  
S. M. Lenzi ◽  
...  
Keyword(s):  
Shell Model ◽  
High Spin ◽  
Spin States ◽  
High Spin States ◽  
Model Interpretation

High-spin states inTc94and the shell-model interpretation

1995 ◽  
Vol 51 (5) ◽  
pp. 2809-2812 ◽  
Author(s):  
S. S. Ghugre ◽  
S. Naguleswaran ◽  
R. K. Bhowmik ◽  
U. Garg ◽  
S. B. Patel ◽  
...  
Keyword(s):  
Shell Model ◽  
High Spin ◽  
Spin States ◽  
High Spin States ◽  
Model Interpretation

Shell model study of high spin states in theN=50 nucleus93Tc

1994 ◽  
Vol 349 (1) ◽  
pp. 33-37 ◽  
Author(s):  
S. S. Ghugre ◽  
S. B. Patel ◽  
R. K. Bhowmik
Keyword(s):  
Shell Model ◽  
High Spin ◽  
Spin States ◽  
High Spin States ◽  
Model Study

Projected shell model description for high-spin states in neutron-rich Fe isotopes

2009 ◽  
Vol 80 (5) ◽  
Author(s):  
Yang Sun ◽  
Ying-Chun Yang ◽  
Hong-Liang Liu ◽  
Kazunari Kaneko ◽  
Munetake Hasegawa ◽  
...  
Keyword(s):  
Shell Model ◽  
High Spin ◽  
Model Description ◽  
Spin States ◽  
Projected Shell Model ◽  
High Spin States ◽  
Fe Isotopes

scholarly journals Shell-Model Calculation of High-Spin States in Neutron-Rich Cr and Fe Isotopes

2015 ◽  
Author(s):  
Tomoaki Togashi ◽  
Noritaka Shimizu ◽  
Yutaka Utsuno ◽  
Takaharu Otsuka ◽  
Michio Honma
Keyword(s):  
Shell Model ◽  
Model Calculation ◽  
High Spin ◽  
Shell Model Calculation ◽  
Spin States ◽  
High Spin States ◽  
Fe Isotopes
Sign in / Sign up

Export Citation Format

Share Document