Angular Correlation of the Gamma-Rays Emitted from the Excited States ofA38

1950 ◽  
Vol 80 (1) ◽  
pp. 115-116 ◽  
Author(s):  
Rolf M. Steffen
Keyword(s):  
Angular Correlation ◽  
Excited States ◽  
Gamma Rays

Nuclear g Factors in 55Fe

1973 ◽  
Vol 51 (7) ◽  
pp. 707-712 ◽  
Author(s):  
P. G. Kerr ◽  
A. W. Gibb ◽  
J. A. Cameron
Keyword(s):  
Excited States ◽  
Gamma Rays ◽  
Target Material ◽  
Internal Field ◽  
Angular Distributions ◽  
Mixing Ratios ◽  
Decay Gamma ◽  
G Factors

The (α,n) reaction on natural chromium has been used to study levels in 55Fe up to 2.5 MeV excitation. Intensities and angular distributions of the decay gamma rays were measured, yielding branching and E2/M1 mixing ratios. In a magnetized target of the alloy Cr20Fe80, the rotation of the angular distributions was observed. Using recently determined lifetimes for the excited states and the average internal field of 277 kOe measured in the target material by Mössbauer absorption, the following g factors are obtained:[Formula: see text]

Nuclear alinement of manganese-56

1959 ◽  
Vol 250 (1263) ◽  
pp. 550-561 ◽  
Keyword(s):  
Angular Distribution ◽  
Excited State ◽  
Angular Correlation ◽  
Excited States ◽  
Daughter Nucleus ◽  
Γ Radiation ◽  
Mixing Ratios ◽  
First Excited State ◽  
Γ Rays ◽  
Coincidence Measurements

The present work demonstrates the feasibility of alining manganese-56 produced by neutron irradiation of a nickel fluosilicate crystal containing stable 55 Mn. Measurements were made of the angular distribution of the γ-radiation from the alined 56 Mn and also of the angular correlation of the γ-rays from this isotope. By combining the results it is possible to establish uniquely as 2 the spins of the states of the daughter nucleus of 56 Fe at 2.66 and 2.98 MeV. The mixing ratios δ ( E 2/ M 1) for the 1.81 and 2.13 MeV γ-rays to the first excited state are shown to be 0.19 ± 0.02 and — 0.28 ± 0.02. The spectrum of the γ-radiation was studied with a scintillation spectrometer and this leads to the following relative intensities; 0.845 MeV (100%), 1.81 MeV (27 ± 3%), 2.13 MeV (15 ± 3%), 2.55 MeV (1.2 ± 0.2%), 2.66 MeV (0.65 ± 0.1%), 2.98 MeV (0.35 ± 0.1%) and 3.4 MeV (0.22 ± 0.05%). Coincidence measurements suggest that the 2.55 and 3.4 MeV γ-rays are due to de-excitation of a level at about 3.4 MeV which decays both to the ground and first excited states. A spin of 2 for this state is proposed.

Angular Correlation of the Gamma Rays fromMn56

1953 ◽  
Vol 92 (4) ◽  
pp. 904-906 ◽  
Author(s):  
F. R. Metzger ◽  
W. B. Todd
Keyword(s):  
Angular Correlation ◽  
Gamma Rays

A study of some excited states of 19F by an angular correlation technique

1966 ◽  
Vol 78 (2) ◽  
pp. 298-318 ◽  
Author(s):  
M.F. Thomas ◽  
J.S. Lopes ◽  
R.W. Ollerhead ◽  
A.R. Poletti ◽  
E.K. Warburton
Keyword(s):  
Angular Correlation ◽  
Excited States ◽  
Correlation Technique

GAMMA-RAY ANGULAR CORRELATIONS FROM ALIGNED NUCLEI PRODUCED BY NUCLEAR REACTIONS

1961 ◽  
Vol 39 (6) ◽  
pp. 788-824 ◽  
Author(s):  
A. E. Litherland ◽  
A. J. Ferguson
Keyword(s):  
Angular Correlation ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Nuclear Reactions ◽  
Residual Nucleus ◽  
Incident Beam ◽  
Nuclear Spectroscopy ◽  
Population Parameters ◽  
Axially Symmetric ◽  
Angular Correlations

Two general procedures for the measurement and analysis of angular correlations of gamma radiations from nuclear reactions are described which have wide applications in nuclear spectroscopy for the determination of spins and gamma-ray multipolarities. Cases can be studied by these methods when the reaction proceeds through a compound state too complex to allow the usual analysis to be made, for example where several levels overlap or where direct interaction is dominant. The basis of these procedures is to exploit the simplifications brought about by making the reacting system axially symmetric. A sharp gamma-ray-emitting state formed in such a system can be regarded as aligned and described in terms of a relatively small number of population parameters for the magnetic substates. In the first procedure, a state Y* is prepared by a nuclear reaction X(h1h2) Y* in which h2 is unobserved. The state Y* has axial symmetry about the beam axis. From coincidence angular correlation measurements of two cascade gamma rays from Y*, the unknown population parameters for Y* together with the nuclear spins and gamma-ray multipolarities can be determined. In the second procedure, h2 is measured in a small counter at 0° or 180° relative to the incident beam. It is then shown that the quantum numbers of the magnetic substates of Y* which can be populated do not exceed the sum of the spins of X, h1, and h2. In cases where the sum of the spins does not exceed [Formula: see text], the angular correlation of the gamma rays from the aligned state depends only upon the properties of the states in the residual nucleus. Theoretical expressions for angular correlations from aligned states are given, together with a method whereby existing extensive tables of coefficients can be used to calculate them. The results of two recent experiments are discussed as examples.

AN ILLUSTRATION OF A TYPE OF TRIPLE CORRELATION MEASUREMENT WHICH CAN BE EASILY INTERPRETED

1960 ◽  
Vol 38 (7) ◽  
pp. 927-940 ◽  
Author(s):  
A. E. Litherland ◽  
G. J. McCallum
Keyword(s):  
Angular Correlation ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Residual Nucleus ◽  
Incident Beam ◽  
Electric Quadrupole ◽  
Final States ◽  
Angular Correlations ◽  
Mixing Ratios ◽  
Triple Correlation

The Mg26(He4, nγ)Si29 reaction has been used to illustrate the simplifications introduced in the interpretation of triple angular correlations by choosing a target and bombarding particles of zero spin and by observing the emitted particles, in this case neutrons, in a counter fixed at 0° to the beam. The angular correlations of the gamma rays with respect to the incident beam then depend only upon the properties of the final states in the residual nucleus. The angular correlation of the electric quadrupole 2.03-Mev gamma ray is predicted uniquely by theory and this prediction has been verified experimentally. The angular correlations of the 1.28-Mev and 2.43-Mev gamma rays have yielded for the E2/M1 amplitude mixing ratios +0.25 ± 0.05 or −3.4 ± 0.5 and −0.26 ± 0.08 or −1.10 ± 0.16 respectively. In addition, the experiment provides an illustration of the value of the recently discovered technique of neutron – gamma-ray discrimination in an organic scintillator.

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