Decay of 142La

1971 ◽  
Vol 49 (9) ◽  
pp. 1179-1185 ◽  
Author(s):  
S. L. Tong ◽  
W. V. Prestwich ◽  
K. Fritze
Keyword(s):  
Excited States ◽  
Beta Decay ◽  
Gamma Rays ◽  
Proportional Counter ◽  
Decay Scheme ◽  
Branching Ratios ◽  
Coincidence Measurement

The energies of the gamma rays following the beta decay of 92.5 min 142La have been precisely measured, and a coincidence measurement with a NaI(Tl) and Ge(Li) system was made by gating the NaI(Tl) at 641 keV. With these results, the decay scheme of 142Ce derived by Prestwich and Kennett was modified. The beta branching ratios of the decay of 142La to the ground and excited states of 142Ce have also been obtained by simultaneous gamma and 4π beta countings with a 3 in. × 3 in. NaI(Tl) detector and a 4π-proportional counter.

LOW-SPIN STATES OF 83Rb EXCITED IN THE 83Sr(β++EC)83Rb DECAY

2000 ◽  
Vol 09 (06) ◽  
pp. 471-485 ◽  
Author(s):  
XIAOHAN YU ◽  
SHUANGHUI SHI ◽  
JIAHUI GU ◽  
JINGYI LIU ◽  
WENXIN LI ◽  
...  
Keyword(s):  
Excited States ◽  
Gamma Rays ◽  
Half Life ◽  
Beam Energy ◽  
Decay Scheme ◽  
Branching Ratios ◽  
Spin States ◽  
New Information ◽  
Hpge Detectors ◽  
Γ Ray

Gamma-rays from the 83 Sr (β++ EC )83 Rb decay have been investigated with Compton suppressed HpGe detectors. The activity was produced via the 85 Rb (p,3n) reaction at 27.1 MeV beam energy. Singles in multispectra mode and γ–γ coincidence experiments were performed. Approximately 190 transitions including 94 new transitions and 19 new levels were assigned to 83 Rb , based on their measured half-life and/or observation in coincidence with well-known lines. A decay scheme has been constructed consisting of 41 excited states and 180 transitions in 83 Rb . Additional new information has been obtained on γ-ray branching ratios, log ft values, spins and parities.

The Decay of 124Sb

1974 ◽  
Vol 52 (5) ◽  
pp. 406-419 ◽  
Author(s):  
J. R. Johnson ◽  
K. C. Mann
Keyword(s):  
Beta Decay ◽  
Gamma Rays ◽  
Decay Scheme ◽  
Gamma Ray ◽  
Branching Ratios ◽  
Conversion Electrons ◽  
First Time

The gamma rays, beta rays, and conversion electrons emitted in the beta decay of 124Sb → 124Te have been observed using Ge(Li) and Si(Li) detectors both singly and in coincidence. The measured energies and intensities of the different transitions involved in this decay together with the coincidence results have allowed us to construct the decay scheme. The spin of most of the states and the parity of all of the states of 124Te populated in this decay have been deduced, some of them for the first time, and others as confirmations of previous assignments. We have also been able to assign collective parameters to many of these states, in terms of the vibrational model of nuclei, from the reduced branching ratios calculated from the gamma-ray intensities.

scholarly journals Nuclear Structure Investigations of some Medium-Weight Isotopes

2021 ◽  
Author(s):  
◽  
Gavin Wallace
Keyword(s):  
Nuclear Structure ◽  
Beta Decay ◽  
Cross Section ◽  
Gamma Rays ◽  
Half Life ◽  
Decay Scheme ◽  
Gamma Ray ◽  
Calculated Cross Section ◽  
Beta Spectrum ◽  
Gamma Ray Detectors

<p>This thesis describes the methods and results of investigations made to determine the decay schemes of three short-lived isotopes 112Ag, 114Ag and 116Ag. A total of 76 gamma-rays was observed with a Ge(Li) detector in the gamma-radiation which follows the Beta-decay of 112Ag to levels of 112Cd. gamma- gamma coincidence and angular correlation measurements were made with Ge(Li)-NaI(T1) and NaI(T1)-NaI(T1) systems. A decay scheme consistent with the present data is proposed. Cross sections for the reactions 112Cd(n,p)112Ag and 115In(n, alpha)112Ag were measured, and the half-life of the 112Ag decay was found to be 3.14 plus-minus 0.01 hr. The decay scheme of 114Ag was studied with Ge(Li) gamma-ray detectors and plastic Beta-ray detectors. 9 of the 11 gamma-rays observed in the decay were incorporated into 114Cd level structure previously determined by conversion electron measurements on the 113Cd(n,gamma)114Cd reaction. The endpoint energy of the Beta-decay was determined as 4.90 plus-minus 0.26 MeV; no branching was evident in the Beta-spectrum. A decay scheme is proposed for which the Beta-branching was deduced from the measured gamma-ray yield and a calculated cross section value for the 114Cd(n,p)114Ag reaction. The 114Ag half-life was determined as 4.52 plus-minus 0.03 sec; a search for a previously reported isomeric state of 114Ag was unsuccessful. Ge(Li) and NaI(T1) gamma-ray detectors were used to study the direct and coincidence spectra that result from the decay of 116Ag, the half-life of which was found to be 2.50 plus-minus 0.02 min. 53 gamma-rays were observed from this decay. The Beta-branching to the 17 excited states of 116Cd in the proposed decay scheme was derived from the measured gamma-ray yield and a calculated cross section value for the 116Cd(n,p)Ag reaction. Spin and parity assignments for ihe energy levels of 116Cd are made. An investigation of the applicability of two collective models to nuclear structure typical of the Cd nuclei studied demonstrated that one of the models was misleading when applied to vibrational nuclei. A potential function was developed in the other model to extend the investigation to include a study of the transition between extremes of collective motion. This was used to examine the correspondence between nuclear level schemes representative of rotational and vibrational excitations.</p>

Levels in 89Rb Populated by the Beta Decay of 89Kr

1972 ◽  
Vol 50 (22) ◽  
pp. 2741-2752 ◽  
Author(s):  
W. F. S. Poehlman ◽  
B. Singh ◽  
M. W. Johns
Keyword(s):  
Excited States ◽  
Beta Decay ◽  
Gamma Rays ◽  
Large Volume ◽  
Ground State ◽  
Level Scheme ◽  
Gamma Coincidence ◽  
Coincidence Data ◽  
Coincidence Arrangement

The decay of 3.2 min 89Kr has been investigated with small and large volume Ge(Li) detectors used singly and in a dual parameter coincidence arrangement. A total of 162 gamma rays are identified with the decay of this isotope, 120 of which are placed in a level scheme on the basis of gamma–gamma coincidence evidence and the energy differences between established levels. Levels at 220.9, 497.7, 577.3, 586.1, 930.7, 931.5, 997.6, 1195.5, 1324.6, 1530.1, 1533.6, 1694.1, 1822.1, 1998.9, 2160.5, 2401.5, 2598.5, 2867.2, 3099.7, 3329.9, 3363.1, 3372.1, 3534.1, 3719.3, 4145.1, 4217.4, 4340.9, and 4487.5 keV are well established by coincidence data and many energy sums. The levels proposed at 2783.4, 3429.7, 3456.6, 3978.4, 4058.4, and 4406.5 keV are less securely established. The most probable spins of the ground state and the first two excited states arc 3/2−. 5/2− and 1/2− respectively. Improved energies and intensities of the gamma rays from the decay of 15 min 89Rb have also been determined.

Level structure of 88Rb

1970 ◽  
Vol 48 (6) ◽  
pp. 753-758 ◽  
Author(s):  
H. Lycklama ◽  
T. J. Kennett
Keyword(s):  
High Resolution ◽  
Beta Decay ◽  
Gamma Rays ◽  
Decay Scheme ◽  
Level Structure ◽  
Good Efficiency

The beta decay of 2.8 h 88Kr has been investigated using a high-resolution and good efficiency 40 cm3 coaxial Ge(Li) counter. A total of 40 gamma rays were detected and determined to belong to the beta decay of 88Kr. All but one of these were placed in a consistent decay scheme. As a result it was possible to give a plausible interpretation to the level structure of 88Rb.

Study of thermal neutron capture in potassium

1970 ◽  
Vol 48 (10) ◽  
pp. 1109-1129 ◽  
Author(s):  
L. V. Johnson ◽  
T. J. Kennett
Keyword(s):  
Thermal Neutron ◽  
Excited States ◽  
Neutron Capture ◽  
Decay Scheme ◽  
Gamma Ray ◽  
Branching Ratios ◽  
Experimental Results ◽  
Thermal Neutron Capture ◽  
Gamma Coincidence

The 39K(n,γ)40K reaction has been studied using a Ge(Li) and a Ge(Li)–Ge(Li) spectrometer. A total of 252 gamma-ray transitions has been observed and a gamma–gamma coincidence matrix involving 62 transitions has been established. A decay scheme based on the experimental results is deduced for 202 of the observed gamma-ray transitions. Spins and parities of some excited states have been estimated from the deduced branching ratios. The neutron separation energies of the 40K and 42K nuclei have been determined as 7800.5 ± 0.2 and 7535.2 ± 1.5 keV respectively.

Levels of 186W from the Decay of 186Ta

1973 ◽  
Vol 51 (3) ◽  
pp. 241-256 ◽  
Author(s):  
S. C. Gujrathi ◽  
S. K. Mark
Keyword(s):  
Experimental Data ◽  
High Resolution ◽  
Excited States ◽  
Gamma Rays ◽  
Decay Scheme ◽  
Transition Probabilities ◽  
Recent Experimental Data ◽  
Particle State ◽  
Quasi Particle ◽  
Coincidence Data

Gamma rays from the decay of 10.5 min 186Ta have been studied using high resolution Ge(Li) detectors. More than 90 gamma rays have been observed. Several photo-peaks previously reported as single lines were found to be close doublets. The results of this study have been correlated with the published γ–γ coincidence data and the recent (d,d′) reaction work and a decay scheme for 186Ta has been constructed. The scheme incorporates more than 85 transitions among 23 excited states in 186W. The level at 1661 keV has been discussed in terms of a two-proton quasi-particle state arising from the Nilsson orbitals Ωπ[NnzΛ] = 7/2+[404] and 1/2+[411]. Several transition probabilities have been extracted and compared with other recent experimental data and with the calculations of Kumar and Baranger as well as with the predictions of various phenomenological models.

THE DECAY OF Os191 AND Os193

1958 ◽  
Vol 36 (10) ◽  
pp. 1409-1429 ◽  
Author(s):  
S. V. Nablo ◽  
M. W. Johns ◽  
R. H. Goodman ◽  
A. Artna
Keyword(s):  
Excited States ◽  
Gamma Rays ◽  
Cross Sections ◽  
Decay Scheme ◽  
Internal Conversion ◽  
Gamma Ray ◽  
Internal Conversion Coefficients ◽  
Gamma Coincidence ◽  
Conversion Coefficients ◽  
Activation Cross Sections

The beta- and gamma-ray spectra of Os191 and Os193 have been studied with a magnetic beta-ray spectrometer, scintillation spectrometers, and coincidence circuits. The 14-hour isomer of Os191 decays via a 0.0742-Mev (M3) transition. Gamma rays of energy 0.0418 (100%, E3), 0.0809 (1%, M1 + E2), 0.1287 (100%, M1 + E2), and 0.1858 (0.1%) Mev have been found to be associated with the 14.6 ± 0.3 day decay of Os191 and an extension of the accepted decay scheme proposed. The following 19 transitions have been associated with the 31.5 ± 0.5 hour decay of Os193: 0.0730 (14%), 0.1068 (~1%), 0.1393 (10%), 0.180 (0.3%), 0.196 (0.1%), 0.243 (~0.2%), 0.2485 (0.3%), 0.2514 (0.4%), 0.278 (0.6%), 0.2810 (1.6%), 0.2885 (0.3%), 0.2994 (0.4%), 0.314 (0.3%), 0.3218 (1.7%), 0.3620 (0.6%), 0.3878 (1.6%), 0.4604 (4.1%), 0.4857 (0.3%), and 0.5585 (2.2%). The internal conversion coefficients for all the stronger transitions suggest that they are M1 + E2 in character. The decay energy of Os193 is 1.132 ± 0.005 Mev. Fermi analyses and beta–gamma coincidence experiments have established excited states of Ir193 at 0.073, 0.139, 0.281, 0.362, 0.460, and 0.559 Mev above the ground state. Six otherwise unclassified weak gamma rays can be accommodated if levels at 0.247, 0.315, and 0.613 Mev are included in the decay scheme.The activation cross sections of Os184 and Os190 are (2.2 ± 0.5) × 103and 5.3 ± 2 barns respectively, relative to Seren's value of 1.6 ± 0.4 barns for Os192.

Lifetimes and decay modes of low-lying levels in 26Mg and 26Al

1968 ◽  
Vol 46 (9) ◽  
pp. 1035-1050 ◽  
Author(s):  
O. Häusser ◽  
T. K. Alexander ◽  
C. Broude
Keyword(s):  
Excitation Energy ◽  
Excited States ◽  
Gamma Rays ◽  
Doppler Shift ◽  
Bound States ◽  
Branching Ratios ◽  
Decay Modes ◽  
Rotational Bands ◽  
Decay Properties

Several bound states with excitation energy up to 7 MeV were studied in 26Mg, using the 26Mg(p, p′γ) reaction. The attenuated Doppler shift of the de excitation gamma rays was observed with a Ge(Li) spectrometer. The extracted lifetime estimates and branching ratios for 15 excited states suggest that the rotational bands, built on different intrinsic states, are mixed considerably. Incidental information on lifetimes and decay properties of states in 26Al is also presented.

SPINS OF EXCITED STATES OF Os188

1959 ◽  
Vol 37 (6) ◽  
pp. 755-774 ◽  
Author(s):  
W. J. King ◽  
M. W. Johns
Keyword(s):  
Angular Correlation ◽  
Excited States ◽  
Beta Decay ◽  
Decay Scheme ◽  
Gamma Ray ◽  
Correlation Data ◽  
Conversion Coefficients

Seven excited states of Os188 populated through the beta decay of Re188 have been studied by gamma–gamma angular correlation experiments. The data for the various cascades fit the following theoretical functions: (all gamma-ray energies are in kev and the description following each cascade refers to the first transition) 478–155 (2–2–0, 99.7% E2, δ +ve), 931–155 (0–2–0), 672–633 (2–2–0), 97% M1, δ −ve or 3–2–0, 94% M1, δ −ve or conceivably 4–2–0), 828–633 (2–2–0, 98% M1, δ −ve or conceivably 3–2–0, 80% M1, δ −ve), 1132–633 (0–2–0), and 1308–633 (2–2–0, 98% M1, δ −ve). Some attenuation occurred in the correlations involving the 155-kev gamma ray. The K-conversion coefficients for the 478- and 633-kev transitions have been measured as 0.023 ± 0.003 and 0.010 ± 0.002 respectively, confirming the E2 character for these transitions obtained by angular correlation. These results, coupled with data concerning log ft values and gamma-ray intensities, lead to the following spin and parity assignments for levels in Os188: 155 (2+), 633 (2+), 1086 (0+), 1306 (2+ or 3+), 1461 (2+), 1765 (0+), 1941 (2+), and 1958 (1+ or 2+).The 631–137 correlation data in Os186 was found to fit an attenuated 2–2–0 function with the first transition 99% E2 and δ −ve. This result supports the established decay scheme for this nucleus.

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