Proton?Capture Gamma Rays from Nitrogen?13

1962 ◽  
Vol 15 (3) ◽  
pp. 443 ◽  
Author(s):  
AW Parker ◽  
GG Shute
Keyword(s):  
Angular Distribution ◽  
Excited State ◽  
Elastic Scattering ◽  
Gamma Rays ◽  
Ground State ◽  
Recent Experiment ◽  
Gamma Ray ◽  
Angular Distributions ◽  
Proton Capture ◽  
Yield Curves

From a recent experiment in this laboratory (Shute et al. 1962) on the elastic scattering of protons from 12C, resonance levels (E13N, J1t) of 13N were obtained at the laboratory bombarding energies (Ep) shown in Table 1. To confirm these results, an investigation of the yield and angular distribution of gamma rays from the reaction 12C(p'YO)13N and 12C(p'Yl)13N was undertaken. Accordingly, the theoretical angular distributions, W(8), for the gamma ray (Yo) to the ground state of 13Na-) and also for the gamma ray (Yl) to the 1st excited state of 13Na+) were evaluated on the assumptions that overlap of levels in 13N is small and lowest order multipoles are involved. As angular distributions are parity insensitive, these were found to be identical for the two gamma rays expected. The simpler of these angular distributions are also shown on the table. The expected angular distributions indicate that 90� is a suitable angle for yield curves.

ANGULAR DISTRIBUTIONS IN GAMMA–ALPHA REACTIONS IN THE NUCLEI OF NUCLEAR EMULSIONS

1965 ◽  
Vol 43 (6) ◽  
pp. 1015-1019 ◽  
Author(s):  
Jan P. Roalsvig
Keyword(s):  
Angular Distribution ◽  
Excited State ◽  
Ground State ◽  
Intensity Ratio ◽  
Alpha Particles ◽  
Angular Distributions ◽  
Nuclear Emulsions

The angular distribution for alpha particles produced by (γ, α) reactions in the nuclei of nuclear emulsions has been measured. For the reaction 16O(γ, α)12C, in which the 12C nucleus is left in its ground state (J = 0+, T = 0), through an excited state at 12.5 MeV in 16O, the angular distribution is in agreement with a mixture of E1 and E2 interactions, with an E2/E1 intensity ratio of 0.50. For the same reaction, through an excited state at 14.3 MeV in 16O, the angular distribution is best represented by a pure E2 interaction.

Studies of nuclear collisions involving 8 MeV deuterons by the photographic method - IV. Angular distributions of the particles produced by the bombardment of helium and oxygen

1952 ◽  
Vol 210 (1103) ◽  
pp. 534-543 ◽  
Keyword(s):  
Excited State ◽  
Elastic Scattering ◽  
Experimental Technique ◽  
Ground State ◽  
Angular Distributions ◽  
Photographic Method ◽  
Nuclear Collisions ◽  
Nuclear Processes

An experimental technique described previously has been used to study the angular distributions of the products of nuclear processes occurring when helium and oxygen are bombarded by 8 MeV deuterons. Results on the elastic scattering of deuterons by helium and oxygen nuclei, and on the reactions 4 He ( d,p ) 5 He and 16 O ( d,p ) 17 O, are presented and discussed. The results for the two groups of protons from the latter reaction allow it to be established that the ground state of 17 O has spin 5/2 or 3/2 and even parity, while the 0·88 MeV excited state has spin ½ and even parity.

THE ANGULAR DISTRIBUTION OF GAMMA RAYS IN THE C12(p,p′γ) REACTION

1953 ◽  
Vol 31 (2) ◽  
pp. 189-193 ◽  
Author(s):  
H. E. Gove ◽  
N. S. Wall
Keyword(s):  
Angular Momentum ◽  
Angular Distribution ◽  
Excited State ◽  
Proton Beam ◽  
Gamma Rays ◽  
Ground State ◽  
Expansion Formula ◽  
First Excited State ◽  
Incoming Proton

Protons of 7.1 Mev. energy from the MIT cyclotron have been used to investigate the angular distribution of gamma rays from the C12(p,p′γ) reaction with respect to the incoming proton beam. These gamma rays result from transitions between the first excited state of C12 at 4.45 Mev. and the ground state. The resulting distribution can be fitted by the expansion[Formula: see text]which is consistent with an assignment of two for the angular momentum of the first excited state of C12.

14.—Ground State Rotational Bands in 158Dy, 160Dy and 162Dy

1972 ◽  
Vol 70 ◽  
pp. 155-163 ◽  
Author(s):  
G. T. Ewan ◽  
G. I. Andersson
Keyword(s):  
Gamma Rays ◽  
Ground State ◽  
Gamma Ray ◽  
Angular Distributions ◽  
Rotational Bands ◽  
Weak Evidence ◽  
Gamma Coincidence ◽  
Inertia Model ◽  
Coincidence Spectra ◽  
Variable Moment

SynopsisLevels in the ground state bands of 158Dy, 160Dy and 162Dy have been populated by (α, 2n) reactions on metallic targets of separated 156Gd, 158Gd and 160Gd isotopes. Two Ge(Li) detectors were used to study singles gamma-ray spectra, gamma-ray angular distributions, gamma-gamma coincidence spectra and relative yields of gamma-rays for bombarding energies from 20 to 27 MeV. Transitions from all levels in the ground state bands up to the 12+ member were identified and the following level energies in keV established: 158Dy: 0 (0+), 99·0 (2+), 317·4 (4+), 637·9 (6+), 1044·1 (8+), 1520·1 (10+) and 2049·4 (12+); 160Dy: 0 (0+), 86·7 (2+), 283·7 (4+), 581·4 (6+), 967·4 (8+), 1429·0 (10+), 1951·7 (12+); 162Dy: 0 (0+), 80·7 (2+), 265·7 (4+), 548·5 (6+), 921·1 (8+), 1374·8 (10+) and 1901·0 (12+). There is weak evidence for the 14+ levels in 158Dy and 160Dy. The level energies are compared with calculated values using the variable moment of inertia model.

scholarly journals Relative Intensity of the 17·2 and 14·3 MeV Gamma Rays from the 7Li(p,G)8Be Reaction

1960 ◽  
Vol 13 (2) ◽  
pp. 204 ◽  
Author(s):  
B Mainsbridge
Keyword(s):  
Excited State ◽  
Gamma Rays ◽  
Relative Intensity ◽  
Principal Components ◽  
Ground State ◽  
Intensity Ratio ◽  
Proton Capture ◽  
First Excited State

Radiation from proton capture in 7Li is known to consist of two principal components of energy (17�2+~.Ep) and (14'3+~Ep)MeV, corresponding to transitions to the ground state and first excited state of sBe respectively (Walker and McDaniel 1948). Resonances in the reaction are known to exist at Ep=441 keY, 1�03 and 2�1 MeV (Bonner and Evans 1948; Kraus 1954; Price 1954) and the relative intensity of the two y-rays is known to vary in the neighbourhood of the 441 keY resonance (Campbell 1956). It is not known if the intensity ratio varies in the region of the 1030 keY resonance and this experiment was designed to repeat the measurements of Campbell and extend the investigation to the higher resonance.

Positive-Parity Bands in 29Si

1971 ◽  
Vol 49 (10) ◽  
pp. 1263-1274 ◽  
Author(s):  
A. A. Pilt ◽  
R. H. Spear ◽  
R. V. Elliott ◽  
J. A. Kuehner
Keyword(s):  
Angular Distribution ◽  
Excited State ◽  
Linear Polarization ◽  
Ground State ◽  
Gamma Ray ◽  
Positive Parity ◽  
Rotational Bands ◽  
Mixing Ratios ◽  
First Excited State ◽  
Nilsson Model

A study has been made of several high spin members of the ground state (Kπ = 1/2+) and first-excited state (Kπ = 3/2+) rotational bands in the presumed oblate nucleus 29Si. Gamma-ray angular distribution and linear polarization measurements have confirmed the spin and parity of the 4081 keV level to be 7/2+, and levels at 4742 and 5283 keV have been shown to have Jπ = 9/2+ and (7/2+, 3/2+) respectively. Branching and mixing ratios for the transitions from these states have also been determined; in conjunction with previously measured lifetimes, transition strengths are calculated. The results are compared with the predictions of a Nilsson-model calculation including the effects of coriolis mixing of the low-lying positive parity bands.

Study of the Ep = 1.724 MeV Resonance in the 27Al(p, γ) 28Si Reaction

1971 ◽  
Vol 49 (6) ◽  
pp. 685-703 ◽  
Author(s):  
S. T. Lam ◽  
A. E. Litherland ◽  
R. E. Azuma
Keyword(s):  
Ground State ◽  
Gamma Ray ◽  
Branching Ratios ◽  
Thick Target ◽  
Angular Distributions ◽  
Transition Strength ◽  
Proton Capture ◽  
A Value ◽  
28Si Reaction ◽  
Relative Measurements

The 13.245 MeV level in 28Si has been populated by resonant proton capture at 1.724 MeV in the 27Al(p,γ)28Si reaction. Gamma-ray angular distributions and linear polarizations have been measured respectively with a coaxial and a planar Ge(Li) counter. Branching ratios have been extracted from the angular distributions. Spins have been assigned to the levels of 28Si with the help of the angular distribution and linear polarization results. The spin and parity of the 13.245 and 9.699 MeV levels are most probably 5− with T = 1 and 0 respectively. The assignment Jπ = 4− for the 8.411 MeV level is in agreement with the present data. A spin and parity of 3− for both the 13.245 and 9.699 MeV levels also fits the data but with more adjustable parameters. Arguments are presented to show that these assignments are unlikely. Relative measurements of the gamma-ray yields from a thick target give a value of (7.5 ± 1.5) eV for (2J + 1)ΓγΓp/Γ of the resonance. The M1 transition strength between the 13.245 and the 9.699 MeV levels is then deduced to be (0.7 ± 0.15) W.u. The known properties of the 9.699 MeV level suggest that it may be associated with an E5 oscillation of the ground state of 28Si.

SOME PROPERTIES OF THE 2.23-MEV EXCITED STATE OF P31

1959 ◽  
Vol 37 (1) ◽  
pp. 53-62 ◽  
Author(s):  
A. E. Litherland ◽  
G. A. Bartholomew ◽  
H. E. Gove ◽  
E. B. Paul
Keyword(s):  
Angular Momentum ◽  
Excited State ◽  
Gamma Rays ◽  
Ground State ◽  
Total Angular Momentum ◽  
Gamma Ray ◽  
Triple Correlation ◽  
Compound State ◽  
First Excited State ◽  
Coincidence Measurements

The 2.23-Mev excited state of P31 has been studied by means of the capture gamma rays from the 1.70-Mev resonance in the reaction Si30(pγ)P31. The angular correlation of the ground state gamma ray established that the resonance had total angular momentum 3/2, and triple correlation measurements of the cascading gamma rays from the compound state showed that the angular momentum of the 2.23-Mev state was 5/2. Coincidence measurements showed that the cascade gamma rays from the 2.23-Mev state to the first excited state at 11.27-Mev were [Formula: see text] of the transitions to the ground state.

THE ANGULAR DISTRIBUTION OF 5.6-MeV GAMMA RAYS FROM THE CAPTURE BY 124Sn OF 62-eV NEUTRONS

1965 ◽  
Vol 43 (12) ◽  
pp. 2156-2161 ◽  
Author(s):  
K. G. McNeill ◽  
D. B. McConnell ◽  
F. W. K. Firk
Keyword(s):  
Angular Distribution ◽  
Gamma Rays ◽  
Ground State ◽  
Gamma Ray ◽  
The State

Angular distribution measurements have been made on the near-ground-state gamma-ray transitions from the state in 125Sn excited by the capture by 124Sn of 62-eV neutrons. The distribution is essentially isotropic. In conjunction with other evidence, it is concluded that the capturing state is a p 1/2 state.

Study of Low-Lying Levels in 37Ar

1972 ◽  
Vol 50 (11) ◽  
pp. 1182-1194 ◽  
Author(s):  
P. Taras ◽  
A. Turcotte ◽  
R. Vaillancourt
Keyword(s):  
Angular Distribution ◽  
Gamma Rays ◽  
Linear Polarization ◽  
Ground State ◽  
Solar Neutrino ◽  
Gamma Ray ◽  
Capture Rate ◽  
Mixing Ratio ◽  
Excitation Energies ◽  
Decay Gamma

The properties of the first five excited levels in 37Ar were investigated via the 37Cl(p,n)37Ar reaction at Ep = 3.98, 4.17, 4.38, and 4.81 MeV and via the 34S(α,n)37Ar reaction at Eα = 8.00, 8.50, and 8.60 MeV. The following excitation energies were obtained: Ex = 1409.7 ± 0.4, 1611.5 ± 0.4, 2217.8 ± 0.8, 2491.4 ± 0.8, and 2797.0 ± 0.8 keV. These levels were found to decay almost entirely to the ground state. The angular distribution and the linear polarization of the decay gamma rays of these levels were measured. From these measurements definite spin–parity assignments as well as values of the mixing ratio of the ground state gamma-ray transitions were obtained. These are: Ex(Jπ, δ) = 1612 ([Formula: see text], +0.11 ± 0.02), 2218 ([Formula: see text], 0.0 ± 0.02), 2491 ([Formula: see text]), and 2797 ([Formula: see text], −0.16 ± 0.03 or +8.0 ± 1.5, the value of −0.16 being more probable). The measurements were also consistent with a spin of [Formula: see text] for the 1410 keV level. The results are compared with a recent shell-model calculation and are discussed in the context of the solar neutrino capture rate in 37Cl.

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