Gamma-Ray Angular Correlations and Lifetime Measurements for Some Excited States ofNe21

The 40Ca(α, pγ)43Sc reaction at Eα = 11.8 to 15.5 MeV has been used to investigate the level structure of 43Sc below 4.2 MeV excitation. Level energies and decay schemes were determined from proton–gamma coincidence spectra obtained using an annular surface barrier detector positioned near 180° and two 40 cm3 Ge(Li) detectors. Angular correlations were measured in the same configuration using an array of six 12.7 × 15.2 cm NaI(Tl) detectors mounted on the Chalk River LOTUS goniometer. Twelve new levels were observed in 43Sc and information on the spins, branching ratios, and gamma-ray multipole mixing ratios of these and several other excited states has been obtained. The results are compared with recent theoretical predictions of Johnstone. In particular, levels at 1931 and 2552 keV, 1830 keV and 1883 keV have been tentatively assigned as the 9/2+ and probable 11/2+ members of the kπ = 3/2+ band, the (fp)3, Jπ = 11/2− state, and the 9/2− member of the kπ = 3/2− band, respectively.

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Symmetries in mirror nuclei 31S and 31P

EPJ Web of Conferences ◽

10.1051/epjconf/201819403001 ◽

2018 ◽

Vol 194 ◽

pp. 03001

Author(s):

D. Tonev ◽

G. de Angelis ◽

N. Goutev ◽

S. Iliev ◽

R. Orlandi ◽

...

Keyword(s):

Charged Particle ◽

Excited States ◽

Doppler Shift ◽

Isospin Symmetry ◽

Particle Detector ◽

Lifetime Measurements ◽

Angular Correlations ◽

Doppler Shift Attenuation ◽

First Time

Excited states in mirror nuclei 31S and 31P were populated in the 1n and 1p exit channels, respectively, of the reaction 20Ne + 12C. The beam of 20Ne, with an energy of 33 MeV, was delivered for the first time by the Piave-Alpi accelerator of the Laboratori Nazionali di Legnaro. Angular correlations of coincident pairs and Doppler-shift attenuation lifetime measurements in 31S and 31P were performed using the multidetector array GASP in conjunction with the EUCLIDES charged particle detector. A comparison of the determined B(E1) strengths of the analog mirror 7/2- → 5/2+ transitions indicates the presence of a violation of isospin symmetry.

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EXCITED STATES OF O18 STUDIED BY THE REACTION

Canadian Journal of Physics ◽

10.1139/p61-028 ◽

1961 ◽

Vol 39 (2) ◽

pp. 276-294 ◽

Cited By ~ 11

Author(s):

A. E. Litherland ◽

R. Batchelor ◽

A. J. Ferguson ◽

H. E. Gove

Keyword(s):

Excited States ◽

Gamma Rays ◽

Recent Experiment ◽

Gamma Ray ◽

Electric Quadrupole ◽

Angular Correlations ◽

Small Admixture ◽

First Excited State ◽

Cascade Transition ◽

Crossover Transition

Gamma rays from the excited states of O18 at 3.63 and 3.92 Mev have been observed using the reaction [Formula: see text] at an incident O16 energy of 14 Mev. Both states were observed to emit gamma rays to the 1.98-Mev 2+ first excited state of O18. No evidence for crossover transitions was found and in each case the crossover transition was estimated to be [Formula: see text] of the cascade transition. Angular correlations of the gamma rays were obtained and these strongly support an assignment of spin 0 to the 3.63-Mev state and a spin of 2 for the 3.92-Mev state. These assignments have been confirmed by a recent experiment on the O16(H3, p)O18 reaction which gives the assignments 0+ and 2+ for these two states. Thus the states at 3.55, 3.63, and 3.92 Mev form a triplet with assignments 4+, 0+, and 2+ which strongly resembles the vibrational spectra found in heavier nuclei. However, the measured angular correlations of the gamma rays from the 3.92-Mev state show only a small admixture of electric quadrupole in the 1.94-Mev gamma ray with relative amplitude +0.1 ±.1. A lower limit of ~10−12 seconds on the lifetime of the 3.63-Mev state was obtained from the absence of a doppler shift of the 1.65-Mev cascade gamma ray.

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NUCLEAR g FACTORS OF THE FIRST EXCITED STATES OF 76Se AND 122Te

Canadian Journal of Physics ◽

10.1139/p67-141 ◽

1967 ◽

Vol 45 (5) ◽

pp. 1821-1831 ◽

Cited By ~ 19

Author(s):

J. Murray ◽

T. A. McMath ◽

J. A. Cameron

Keyword(s):

Magnetic Fields ◽

Excited States ◽

Gamma Ray ◽

Iron Alloys ◽

Angular Correlations ◽

G Factors

The nuclear g factors of the first excited states of 76Se and 122Te have been measured by observing the rotation of gamma-ray angular correlations. The perturbing magnetic fields used were the internal fields in dilute iron alloys. The values obtained for the g factors are[Formula: see text]

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EXCITED STATES OF 11C FROM n–γ ANGULAR CORRELATK AND GAMMA BRANCHING RATIOS

Canadian Journal of Physics ◽

10.1139/p66-104 ◽

1966 ◽

Vol 44 (6) ◽

pp. 1213-1223 ◽

Cited By ~ 2

Author(s):

A. S. Rupaal ◽

B. L. White ◽

J. R. Prescott

Keyword(s):

Experimental Study ◽

Excited States ◽

Ground State ◽

Gamma Ray ◽

High Energy ◽

Branching Ratios ◽

Intermediate Coupling ◽

Angular Correlations ◽

Gamma Transitions ◽

Bombarding Energy

An experimental study of excited states of 11C below 6.5 MeV has been made using the 10B (d, nγ)11C reaction at a deuteron bombarding energy of 0.8 MeV. Measurements were made of the n–γ angular correlations of the ground-state gamma transitions from the 6.49- and 4.32-MeV levels, and of the gamma-ray branching ratios from the 6.49-, 4.81-, and 4.32-MeV levels.Theoretical analysis of the n–γ angular correlations suggests that the J values of the 6.49- and 4.32-MeV levels are (3/2), (5/2), or (7/2). The parities of all the states observed in this experiment are already known to be negative from high-energy stripping data. A comparison of the experimental branching ratios with theoretical branching ratios predicted by the intermediate coupling shell model is consistent with the following spin and parity assignments in 11C: ground state (3/2)−, 2.00 MeV (1/2)−, 4.32 MeV (5/2)−, 4.81 MeV (3/2)−, and 6.49 MeV (7/2)−.

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