The decay of 144Pm

1968 ◽  
Vol 46 (19) ◽  
pp. 2181-2187 ◽  
Author(s):  
S. Santhanam

In the electron-capture decay of 144Pm prepared by (p, 2n) reaction on enriched 145Nd, it is shown that, in addition to the well-known energy levels at 696, 1313, and 1789 keV, two new levels exist, one at 2093 keV, and another at 1509 keV. The state at 2093 keV deexcites with the emission of a 304-keV gamma ray to the 6+ level at 1789 keV, and by a crossover transition to the 4+ level at 1313 keV with the emission of a 780-keV gamma ray. The level at 1509 keV leads to the first excited state (2+) at 696 keV with the emission of a gamma ray of energy 813 keV. The intensities of the 780-, 304-, and 813-keV gamma rays are, respectively, 1.5, ≈ 0.1, and 0.5% of that of the 696-keV gamma ray.


1961 ◽  
Vol 39 (2) ◽  
pp. 276-294 ◽  
Author(s):  
A. E. Litherland ◽  
R. Batchelor ◽  
A. J. Ferguson ◽  
H. E. Gove

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.



1970 ◽  
Vol 48 (5) ◽  
pp. 483-488 ◽  
Author(s):  
W. R. Dixon ◽  
R. S. Storey

A search has been made with a Ge(Li) detector for weak gamma-ray transitions in 60Ni following the beta decay of 60Co. Observation of a gamma ray of energy 2158.8 ± 0.4 keV and intensity of about 10−5 per disintegration has confirmed that the 2159-keV level of 60Ni is populated in about 10−4 of the disintegrations. A much stronger peak at 822 keV has been shown to be the single-escape peak of the 1332-keV gamma ray rather than the (2159 → 1332) transition as claimed by Hansen and Spernol. The search for other weak gamma rays in 60Ni was inconclusive, and the mechanism for feeding the 2159-keV level is not clear. As a byproduct of this investigation, the energy of the first excited state of 64Ni is found to be 1345.9 ± 0.3 keV.



1959 ◽  
Vol 37 (1) ◽  
pp. 53-62 ◽  
Author(s):  
A. E. Litherland ◽  
G. A. Bartholomew ◽  
H. E. Gove ◽  
E. B. Paul

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.



1970 ◽  
Vol 48 (12) ◽  
pp. 1514-1517 ◽  
Author(s):  
D. S. Murty ◽  
K. V. Ramana Rao ◽  
P. Jagam ◽  
V. Lakshminarayana

The evidence obtained for the existence of the K X-ray gamma-ray directional correlation by Perepelkin against the predictions of the theory of Dolginov evoked considerable interest in this field. The electron capture decay of 114Inm is used to advantage in the present investigation with a sum-peak-coincidence scintillation spectrometer. The results obtained are consistent with the theory of Dolginov.



1986 ◽  
Vol 77 ◽  
Author(s):  
Kazumi Kasai ◽  
H. Tanaka ◽  
H. Itoh ◽  
T. Oh-Hori ◽  
M. Takikawa ◽  
...  

ABSTRACTThe measurement of Shubnikov-de Haas(SdH) oscillation is proposed as a new technique for evaluating the quality of a heterointerface. The first excited state of 2-dimensional electron energy levels is determined for several samples using the measurements of SdH oscillation. Lower values of the first excited state energy are found for the samples with a low mobility. The low value can be approximately explained in terms of graded interface model.



2020 ◽  
Vol 35 (10) ◽  
pp. 2050062
Author(s):  
Abdullah Engin Çalık ◽  
Kaan Manisa ◽  
Ahmet Biçer ◽  
Mehmet Erdoğan ◽  
Mürsel Şen ◽  
...  

Photonuclear reactions have great importance in understanding the structure of the nuclei. These reactions, performed using the gamma rays obtained by way of bremsstrahlung, are a standard nuclear physics experiment. In this study, a non-enriched barium sample was activated for the first time by using a clinical linear accelerator (cLINACs). The spectrum of barium radioisotopes was obtained by using a gamma spectrometry with a high purity germanium (HPGe) detector. The obtained spectroscopic data were analyzed and energy levels and half-life values together with their uncertainties were obtained. Some energy levels and half-lives of [Formula: see text]Ba were determined with more precision than those of literature values.



1958 ◽  
Vol 36 (1) ◽  
pp. 18-24 ◽  
Author(s):  
J. C. Roy ◽  
T. A. Eastwood ◽  
R. C. Hawkings

Long-lived Bi208 has been observed through its decay by electron capture to the first excited state of Pb208 at 2.61 Mev. It has been produced by the (n, 2n) reaction on Bi209 in the NRX reactor. The half-life of Bi208 has been estimated to be 3 × 104 years, with an uncertainty of a factor of about 2.



1972 ◽  
Vol 5 (5) ◽  
pp. 1738-1751 ◽  
Author(s):  
F. T. Porter ◽  
I. Ahmad ◽  
M. S. Freedman ◽  
R. F. Barnes ◽  
R. K. Sjoblom ◽  
...  


1972 ◽  
Vol 50 (19) ◽  
pp. 2348-2354 ◽  
Author(s):  
S. K. Sen ◽  
D. L. Salie ◽  
E. Tomchuk

The decay of 169Yb was investigated using several Ge(Li) detectors of different sizes. The following gamma rays (energies in keV and intensities within brackets) were definitely identified with the 169Yb decay: 20.7 (0.66 ± 0.04), 63.1 (124 ± 5), 93.6 (7.2 ± 0.3), 109.8 (50 ± 2), 117.3 (0.08 ± 0.04), 118.2 (5.4 ± 0.2), 130.5 (34 ± 2), 156.7 (0.023 ± 0.004), 177.2(59 ± 3), 198.0 (100), 240.4 (0.33 ± 0.02), 261.0 (4.7 ± 0.2), and 307.7 (28 ± 1). The recently reported weak gamma-ray peaks at 515 (0.008 ± 0.002) and 625 (0.010 ± 0.002) were also observed and could not be ruled out as not belonging to 169Yb. The recently reported gamma-ray peaks at 140, 160, 207, 288, 295, 316, 320, 328, 355, 371, 379, 396, and 417 were detected and shown not to be from the decay of 169Yb while those at 218, 229, 285, 304, 335, 388, 411, and 425 were not observed and upper limits were placed on their intensities. The presence of very weak peaks at 515 and 625 establishes the formation of the 633 keV state of 169Tm following electron capture decay of 169Yb as reported by George. (This level has been previously observed only in Coulomb excitation of 169Tm.) The total internal conversion coefficient for the 20.7 keV transition was determined for the first time from the direct measurement of the gamma-ray intensity as 51 ± 10 corresponding to an M1 transition.



1962 ◽  
Vol 15 (3) ◽  
pp. 443 ◽  
Author(s):  
AW Parker ◽  
GG Shute

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.



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