Decay Schemes for the Isomers of 148Pm and the Cross Sections for their Production by Neutron Capture in 147Pm

1971 ◽  
Vol 49 (1) ◽  
pp. 108-117 ◽  
Author(s):  
R. S. Mowatt ◽  
W. H. Walker

The γ-ray spectra arising from the decay of 41-day 148Pmm and 5-day 148Pmg produced by the irradiation of 2.6-year 147Pm in a thermal reactor neutron flux have been measured with a Ge(Li) detector. The absolute probabilities for γ-ray emission were determined from an analysis of the spectra and used to construct an improved decay scheme for the two isomers and to obtain their production cross sections. The 147Pm thermal neutron cross sections obtained after making a small correction for epithermal capture are 84 ± 10 b and 72.4 ± 3.0 b for the production of the 148Pmg and 148Pmm activities respectively, in good agreement with the results of Fenner and Large, but significantly smaller than other recent measurements.

2020 ◽  
pp. 148-153
Author(s):  
A.N. Vodin ◽  
O.S. Deiev ◽  
I.S. Timchenko ◽  
S.N. Olejnik ◽  
A.S. Kachan ◽  
...  

The flux-weighted averaged over the energy range of bremsstrahlung spectrum from reaction threshold up to the maximum energy of γ-ray cross-sections <σ(E)> of the 93Nb(γ,n)92mNb and 93Nb(γ,n)92tNb photonuclear reactions were determined by the gamma-activation method within the end-point bremsstrahlung energies Еmax = 36…91 MeV. Activation of 93Nb targets has been done by a bremsstrahlung flux using an electron beam at the linear accelerator LUE-40 at RDC "Accelerator" NSC KIPT. The γ-ray spectra of irradiated targets were registered using the HPGe detector with an energy resolution of 1.8 keV for the 1332 keV line 60Co. To control the bremsstrahlung flux we used natMo witness-targets and a reaction cross-section of 100Mo(γ,n)99Mo. Obtained experimental cross-sections <σ(E)> of the studied reactions are in good agreement with the theoretical values calculated within TALYS 1.9 code and the results of other authors. The averaged cross-sections <σ(E)> of the 93Nb(γ,n)92mNb and 93Nb(γ,n)92tNb reactions in the energy range 35...45 MeV and > 70 MeV were obtained for the first time.


2002 ◽  
Vol 90 (8) ◽  
Author(s):  
G. L. Molnár ◽  
T. Belgya ◽  
Zs. Révay ◽  
Syed M. Qaim

SummaryAccurate partial gamma-ray production cross sections were determined for the prompt and radioactive product decay gamma rays following cold neutron capture in


1983 ◽  
Vol 61 (4) ◽  
pp. 754-756 ◽  
Author(s):  
Seiichi Shibata ◽  
Paul J. Karol

An unknown γ-ray of energy 112.5 keV was found in zirconium fractions chemically extracted from isotopically enriched molybdenum targets bombarded with 500 and 800 MeV protons. All evidence suggests that the γ-ray is identifiable with the decay of 84Zr to 84Y. A half-life of 25.7 ± 0.5 min was obtained for 84Zr, which is considerably longer than previously reported half-lives. The absolute abundance of the 112.5 keV γ-ray was also determined. Relative production cross sections for 84Zr were calculated using these results and were consistent with the values interpolated from isotopic distribution curves for spallation reactions.


2004 ◽  
Vol 82 (4) ◽  
pp. 263-275 ◽  
Author(s):  
M El-Nadi ◽  
A Abdelsalam ◽  
E A Shaat ◽  
N Ali Mossa ◽  
Z Abou Moussa ◽  
...  

Partial production cross sections of electromagnetic breakup of 32S projectiles at two widely differing energies were measured using an emulsion target. The electromagnetic dissociation represents about 6% and 17% of the total number of nuclear events at Elab/A = 3.7 and 200 GeV, respectively. The experimental electromagnetic cross sections σexpEMD show an energy dependence that is well reproduced by the Weizsacker–Williams approximation. The value of σexpEMD at 200A GeV (with γ >> 1) shows a good agreement with that predicted by the combined model of Pshenichnov et al. Examination of the reactions (γ, p) and (γ, He) reveals that the ratio of 1 p/1 He cross sections is close to unity at Dubna energy (3.7A GeV), while it rapidly increases to 3.0 ± 0.6 at CERN energy (200A GeV). In most of the observed dissociation modes, the total kinetic energy of the fragments in the projectile rest frame is lower than 50 MeV. Nevertheless, it is possible that the contribution of excitation modes of the different multipolarities is determining in this region. PACS No.: 25.70


2017 ◽  
Vol 146 ◽  
pp. 01010 ◽  
Author(s):  
K.L. Malatji ◽  
B.V. Kheswa ◽  
M. Wiedeking ◽  
F.L. Bello Garrote ◽  
C.P. Brits ◽  
...  

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