scholarly journals Luni-solar Variations in the Ionosphere

1964 ◽  
Vol 17 (1) ◽  
pp. 50 ◽  
Author(s):  
RA Duncan
Keyword(s):  
Energy Level ◽  
Neutron Energy ◽  
Gamma Ray ◽  
Angular Distributions ◽  
New Energy ◽  
State Spin ◽  
Gamma Decay ◽  
Coincidence Measurements ◽  
Made In

Neutron-gamma-ray coincidence measurements have been made in the reaction 19F(d,ny),oNe at bombarding energies between 500 and 700 keV. Time offlight determination of neutron energy indicates a new energy level in .oNe at lO� 31 �O' 07 MeV. From angular distributions of the neutrons, and observation of the gamma� decay spectrum of the MeV state, spin and parity of 1 + are inferred for this state.

scholarly journals A New Energy Level in 20Ne at 10·31 MeV

1964 ◽  
Vol 17 (1) ◽  
pp. 56 ◽  
Author(s):  
DG Sargood ◽  
GD Putt
Keyword(s):  
Energy Level ◽  
Neutron Energy ◽  
Gamma Ray ◽  
Angular Distributions ◽  
New Energy ◽  
State Spin ◽  
Gamma Decay ◽  
Coincidence Measurements ◽  
Made In

Neutron-gamma-ray coincidence measurements have been made in the reaction 19F(d,ny),oNe at bombarding energies between 500 and 700 keV. Time offlight determination of neutron energy indicates a new energy level in .oNe at lO� 31 �O' 07 MeV. From angular distributions of the neutrons, and observation of the gamma -decay spectrum of the 10.31 MeV state, spin and parity of 1 + are inferred for this state.

High resolution measurements of the hyperfine structure and determination of a new energy level of Tm I

1997 ◽  
Vol 41 (3) ◽  
pp. 181-185 ◽  
Author(s):  
S. Kröger ◽  
L. Tanriver ◽  
H.-D. Kronfeldt ◽  
G. Guthöhrlein ◽  
H.-O. Behrens
Keyword(s):  
High Resolution ◽  
Energy Level ◽  
Hyperfine Structure ◽  
New Energy

Determination of Long-Life Radiocesiums Cs-134 and Cs-137 in Food by γ-Ray Spectrometry: Interlaboratory Study

1995 ◽  
Vol 78 (5) ◽  
pp. 1244-1251
Author(s):  
Paul R Beuaars ◽  
Remmelt van Duk ◽  
Jos A M Geertsen ◽  
Hans Nootenboom
Keyword(s):  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Gamma Ray ◽  
Fission Products ◽  
Spectrometric Method ◽  
Relative Standard ◽  
Cesium 137 ◽  
Reference Measurements ◽  
Made In

Abstract A gamma-ray spectrometric method for the determination of cesium-134 and cesium-137 in food was studied collaboratively in 13 laboratories, using 8 samples (including 4 blind duplicates) consisting of heather honey, milk, and mixed dried herbs. Low resolution, shielded Tl-activated Nal scintillation detectors were used to measure Cs-137 in the photon energy range 516 to 714 keV and Cs-134 in the range 716 to 880 keV. Results were generally acceptable and no outliers were identified for any sample results. The method worked well in the absence of “fresh” fission products. The method was less appropriate for radiocesium determinations where the activity concentration was <100 Bq/kg at a counting time of 900 s or where the Cs-137/Cs-134 activity-ratio was larger than 10. The accuracy of mean measurements of both isotopes (relative to reference measurements made in one laboratory using a high resolution GeLi detector) was in the range of 98 to 103%. For all samples analyzed, the repeatability relative standard deviation (RSDr) values varied from 4.3 to 11.7% for 2 Cs-134 levels ranging from 121 to 337 Bq/kg and from 2.0 to 7.3% for 4 Cs-137 levels ranging from 210 to 1130 Bq/kg, whereas the reproducibility relative standard deviation (RSDR) values for these levels ranged from 10.7 to 14.9% for Cs-134 and from 4.1 to 7.4% for Cs-137.

Levels in 148Tb excited by the (6,7Li,xn) and (10B,xn) reactions

1979 ◽  
Vol 57 (3) ◽  
pp. 358-367 ◽  
Author(s):  
N. C. Singhal ◽  
M. W. Johns
Keyword(s):  
High Spin ◽  
Internal Conversion ◽  
Gamma Ray ◽  
Angular Distributions ◽  
Spin States ◽  
High Spin States ◽  
Internal Conversion Coefficients ◽  
Conversion Coefficients ◽  
Γ Ray ◽  
Coincidence Measurements

High spin slates in 148Tb have been excited by means of 144Sm(6Li,2n), 144Sm(7Li,3n), and 142Nd(10B,4n) reactions and studied by γ-ray and electron measurements. Gamma-ray singles, excitation functions, angular distributions, internal conversion coefficients, and γ–γ coincidence measurements have been made. A seven-fold gamma–gamma cascade feeding the 9+ isomeric state in 148Tb and originating in a level 4137 keV above that state is strongly excited. The spin and parity assignments are made on the basis of angular distribution and internal conversion coefficients. On the basis of these measurements, the 1006 keV transition is E3 in character; the half-life of the 1006 keV (12−) level is established to be 25 ± 2 ns.These experiments also confirm the existence of a number of high spin states in 148Gd seen by earlier workers.

scholarly journals Resonance phenomena in the interaction of fast neutrons with beryllium and aluminium

1947 ◽  
Vol 192 (1028) ◽  
pp. 114-127 ◽  
Keyword(s):  
Energy Level ◽  
Cross Section ◽  
Neutron Energy ◽  
Cross Sections ◽  
Accurate Determination ◽  
Fast Neutrons ◽  
Transmission Method ◽  
The Cross ◽  
Scattering Cross Sections

The total scattering cross-sections of beryllium and aluminium have been measured by a transmission method for neutrons of energies between 0∙35 and 0∙55 MeV and 1∙8 and 4∙0 MeV. Resonances have been found in the scattering by beryllium at a neutron energy of 2∙6 MeV and in the scattering by aluminium at neutron energies of 2∙4 and 2∙9 MeV. It has been shown that the cross-section for the reaction 9 Be ( n , α ) 6 He also has a resonance at 2∙6 MeV, and an accurate determination of the cross-section for this reaction has been made. A discussion is given of the properties of the energy level in 10 Be responsible for the resonances in the case of beryllium.

Determination of the Gamma-Ray Energy of Parapositronium in Two Gamma Decay

1992 ◽  
Vol 105-110 ◽  
pp. 521-524
Author(s):  
Tian Bao Chang ◽  
H.D. Wang ◽  
Z.Q. Shen ◽  
S.Y. Wang
Keyword(s):  
Gamma Ray ◽  
Gamma Decay

On the careful determination of gamma-ray angular distributions in (α, xnγ) reactions: Example of the reaction

1975 ◽  
Vol 125 (1) ◽  
pp. 53-59 ◽  
Author(s):  
Herbert M. Jäger ◽  
Hans Beuscher ◽  
Walter F. Davidson ◽  
Rainer M. Lieder ◽  
Apostolos Neskakis
Keyword(s):  
Gamma Ray ◽  
Angular Distributions

A study of high spin states in 151Gd

1977 ◽  
Vol 55 (7-8) ◽  
pp. 690-713 ◽  
Author(s):  
H. J. Smith ◽  
M. W. Johns ◽  
G. Løvhøiden ◽  
J. V. Thompson ◽  
J. C. Waddington ◽  
...  
Keyword(s):  
Band Structure ◽  
Rotational Band ◽  
Gamma Ray ◽  
Level Structure ◽  
Negative Parity ◽  
Angular Distributions ◽  
Spin States ◽  
High Spin States ◽  
Conversion Coefficients ◽  
Coincidence Measurements

States in the transitional nucleus, 151Gd, excited by the (α,2n) reaction have been studied by gamma-ray and conversion electron measurements. Gamma-ray energies, intensities, excitation functions, and γ–γ coincidence measurements were used to establish the levels populated. Angular distributions involving measurements at seven angles from 0° to 90° and K-conversion coefficients have been used to make spin and parity assignments.The El character of the 65, 79, 340, 358, 406, and 462 keV transitions, which in the absence of K-conversion data had been tacitly assumed to be M1 by earlier workers leads to a significant revision of their parity assignments and interpretation of the level structure. The negative parity states at 1210, 1463, 1726, 2004, 2295, 2600, 2915, and 3237 keV form a well-developed rotational band based on the 11/2− [505] state at 1210 keV. The properties of this band in this nucleus are compared with those of the same band in a number of nearby nuclei. Two non-interacting negative parity bands with states at 0(7/2−), 706(11/2−), 1435(15/2−), 2078(19/2−), and 379(9/2−), 902(13/2−), 1511(17/2−), 2297(21/2−), respectively, have been found, as well as a number of other negative parity states of spin 7/2, 9/2, and 13/2. A complex positive band structure involving states at 784(11/2+), 852(13/2+), 1116(13/2+), 1346(17/2+), 1364(15/2+), 1677(17/2+), 1851(19/2+), 1853(21/2+), 2197(21/2+), 2325(23/2+), and 2405(25/2+) has been identified. By using a somewhat unusual set of parameters, we have been able to approach a description for the positive parity states in terms of the triaxial model of Meyer-ter-Vehn.

96Tc levels populated in the (α,n) reaction

1988 ◽  
Vol 66 (1) ◽  
pp. 62-78 ◽  
Author(s):  
H. A. Mach ◽  
M. W. Johns
Keyword(s):  
Gamma Ray ◽  
Energy Levels ◽  
Angular Distributions ◽  
Internal Conversion Coefficients ◽  
Microscopic Models ◽  
New Energy ◽  
Conversion Coefficients ◽  
Degree Of Confidence ◽  
High Degree ◽  
Vibrational Features

The levels of odd–odd 96Tc have been investigated using the 93Nb(α,nγ)96Tc reaction at an alpha-beam energy of 14 MeV. The experiments involved singles, gamma–gamma coincidences, detailed excitation functions, gamma-ray angular distributions, measurements of the gamma-ray linear polarization coefficients, and electron internal-conversion coefficients. Spin and parity assignments are given with a high degree of confidence to most of the 105 energy levels, which are interconnected by 251 gamma-ray transitions. In particular, a new energy level at 36.24 keV completes a sextet of lowest lying levels ranging in spin from 2+ to 7+ formed by a coupling of an odd g9/2 proton to an odd d5/2 neutron. The structure of 96Tc shows some vibrational features coexisting with a significant configuration mixing. Thus, a quartet of nuclei at the onset of a deformation region at A ~ 100, 94,95Mo and 95,96Tc, provides a challenging ground for testing of the microscopic models and may give further insight into the nature of the neutron–proton interaction in complex nuclei.

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