Study of the 1459-keV level in 19F by the 19F(p,p′γ)19F reaction

S. T. Lam; A. E. Litherland; J. J. Simpson

doi:10.1139/p70-105

Study of the 1459-keV level in 19F by the 19F(p,p′γ)19F reaction

Canadian Journal of Physics ◽

10.1139/p70-105 ◽

1970 ◽

Vol 48 (7) ◽

pp. 827-833 ◽

Cited By ~ 4

Author(s):

S. T. Lam ◽

A. E. Litherland ◽

J. J. Simpson

Keyword(s):

Angular Distribution ◽

Single Crystal ◽

Linear Polarization ◽

Proton Energy ◽

Branching Ratios ◽

Mixing Ratio ◽

Γ Ray ◽

Good Agreement

The 1459-keV level of 19F was populated by the 19F(p,p′γ)19F reaction at a proton energy of 2.78 MeV. The E2/M1 mixing ratio for the 1459 → 110 keV transition was determined to be [Formula: see text] from a combination of the γ-ray angular distribution and linear polarization and the nuclear lifetime. The γ-ray angular distribution was measured with a coaxial Ge(Li) detector and the γ-ray linear polarization with a planar Ge(Li) detector. The corresponding E2 and M1 transition strengths for a lifetime of 0.084 ± 0.020 ps are found to be [Formula: see text] and 0.10 ± 0.03 W.u. respectively. They are in good agreement with the particle–hole calculations of Benson and Flowers. The branching ratios of the 1459-keV level agree well with those of Poletti et al. The γ-ray transitions from the 1459-keV level provide a good example for demonstrating the usefulness of a single crystal Ge(Li) polarimeter.

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Properties of the 1.763 MeV level in 35Cl

Canadian Journal of Physics ◽

10.1139/p69-204 ◽

1969 ◽

Vol 47 (15) ◽

pp. 1605-1616 ◽

Cited By ~ 7

Author(s):

P. Taras ◽

J. Matas

Keyword(s):

Angular Distribution ◽

Beta Decay ◽

Linear Polarization ◽

Ground State ◽

Unified Model ◽

Mixing Ratio ◽

Polarization Measurements ◽

Good Agreement

Angular distribution and linear-polarization measurements have been performed at the Ep = 3.115 and 3.345 MeV resonances in the reaction 35Cl(p,p′γ)35Cl. The spin and parity of the 1.763 MeV level in 35Cl have been deduced to be 5/2+ while the multipolarity mixing ratio of its decay to the ground state has been found to be δ(E2/M1) = +2.64 ± 0.12. These results confirm that the possible E1 transition from the 3.163 to the 1.763 MeV level in 35Cl is inhibited by a factor of at least 108. The properties of the 1.763 MeV level and the beta decay from 35Ar to the first three levels in 35Cl are found to be in quite good agreement with the predictions of the unified model.

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Etude d'une transition possible à trois multipoles dans la désintégration gamma du niveau à 1612 keV de l'37Ar

Canadian Journal of Physics ◽

10.1139/p76-116 ◽

1976 ◽

Vol 54 (10) ◽

pp. 997-999 ◽

Cited By ~ 1

Author(s):

R. Vaillancourt ◽

P. Taras

Keyword(s):

Angular Distribution ◽

Linear Polarization ◽

Simultaneous Measurement ◽

Beam Axis ◽

Γ Rays ◽

Γ Ray

The γ-ray decay of the 1612 keV level (τ = 6.38 ± 0.15 ns) in 37Ar has been analyzed in terms of a mixture of three multipoles. The data was obtained from the simultaneous measurement of the linear polarization and angular distribution of the decay γ rays, in coincidence with the neutrons emitted along the beam axis, the level being populated via the 34S(α, n)37Ar reaction at Eα = 10.5 MeV. The results definitively eliminate the possibility of the γ rays consisting of a mixture of three multipoles, thereby confirming the Jπ = 7/2− assignment to the level.

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A HIGH RESOLUTION FLAT CRYSTAL SPECTROMETER FOR NEUTRON CAPTURE γ-RAY STUDIES

Canadian Journal of Physics ◽

10.1139/p59-026 ◽

1959 ◽

Vol 37 (2) ◽

pp. 203-231 ◽

Cited By ~ 29

Author(s):

J. W. Knowles

Keyword(s):

Single Crystal ◽

Neutron Capture ◽

Counting Efficiency ◽

Double Crystal ◽

Γ Rays ◽

Γ Ray ◽

Antiparallel Position ◽

Crystal Arrangement ◽

Good Agreement ◽

Soller Slit

A flat crystal diffraction spectrometer, constructed for the measurement of γ-rays resulting from neutron capture, is discussed both experimentally and theoretically. The spectrometer is used either as a single crystal or a double crystal instrument. In the single crystal arrangement a Laue diffracted γ-ray beam from a broad source proceeds through a Soller slit which gives it a 45-second angular divergence, to a sodium iodide scintillation detector. The energy is determined by the angle between the Soller slit and the crystal. The resolution is determined by the Soller slit, and is 4% at 1 Mev when diffracting from the (440) planes of a single germanium crystal. In the two-crystal configuration a γ-ray which is Laue diffracted from the first crystal is further diffracted from a second crystal set in the antiparallel position. The angle between the reflecting planes of the two crystals determines the γ-ray energy. The Soller slit serves only as shielding for the detector in this arrangement. The resolution depends upon the mosaics and thicknesses of the crystals; it is 0.4% at 1 Mev for diffraction from the (211) planes of two calcite crystals, each 23 mm thick and of 1.7- and 0.9-second mosaics respectively. The range of measurement extends from 80 kev to greater than 5 Mev. Where other values of γ-ray energies exist, agreement to within the expected precision, ± 0.2% is obtained. The counting efficiency as a function of energy depends on the integrated reflectivities of the crystals which may be determined at the time of a γ-ray measurement by means of the double crystal arrangement. The integrated reflectivity as a function of energy has been calculated for a number of crystals of known mosaic and throughout the range of measurement, from 0.2 to 5 Mev, good agreement is obtained.

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Properties of the 1.410 and 1.612 MeV Levels in 37Ar and the 1.727 MeV Level in 37Cl

Canadian Journal of Physics ◽

10.1139/p71-146 ◽

1971 ◽

Vol 49 (9) ◽

pp. 1215-1224 ◽

Cited By ~ 9

Author(s):

P. Taras ◽

A. Turcotte ◽

R. Vaillancourt ◽

J. Matas

Keyword(s):

Angular Distribution ◽

Gamma Rays ◽

Linear Polarization ◽

Single Particle ◽

Ground State ◽

Incident Proton ◽

Mixing Ratio ◽

Single Particle Excitation ◽

Decay Gamma

The properties of the 1.410 and 1.612 MeV levels in 37Ar and the 1.727 MeV level in 37Cl were investigated. The levels in 37Ar were populated via the 37Cl(p,n)37Ar reaction and the level in 37Cl via the 37Cl(p,p′)37Cl reaction. The angular distribution and the linear polarization of the decay gamma rays of these levels were measured at incident proton energies of 3.98, 4.17, 4.38, and 4.81 MeV. The results of these measurements are consistent with a spin of 1/2 for the 1.410and 1.727 MeV levels, while they definitely establish the spin and parity of the 1.612 MeV level to be 7/2−. This last level has also been found to decay entirely to the ground state, with a multipolarity mixing ratio δ(E3/M2) = +0.22 ± 0.11. This level has properties quite similar to those of the 7/2− states in 35Cl and 37Cl, indicating that they may all arise from a 1f7/2 single-particle excitation.

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The high spin states in 147Tb excited by the (6Li,3n) reaction

Canadian Journal of Physics ◽

10.1139/p80-213 ◽

1980 ◽

Vol 58 (11) ◽

pp. 1617-1624 ◽

Cited By ~ 8

Author(s):

Tasneem A. Khan ◽

M. W. Johns

Keyword(s):

Angular Distribution ◽

High Spin ◽

Linear Polarization ◽

Level Scheme ◽

Internal Conversion ◽

Gamma Ray ◽

Spin States ◽

Excitation Functions ◽

High Spin States ◽

Γ Ray

High spin states in 147Tb have been excited by means of the 144Sm(6Li,3n) reaction and studied by means of γ-ray and electron measurements. Gamma-ray singles, excitation functions, angular distribution, linear polarization, γ–γ coincidence, and internal conversion measurements have been made. These have led to unambiguous spin and parity assignments to many levels and to lifetime determinations for two states. The resulting level scheme is discussed and compared with recent calculations.

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Band Structure in 21Ne

Canadian Journal of Physics ◽

10.1139/p72-176 ◽

1972 ◽

Vol 50 (12) ◽

pp. 1286-1294 ◽

Cited By ~ 10

Author(s):

A. A. Pilt ◽

R. H. Spear ◽

R. V. Elliott ◽

D. T. Kelly ◽

J. A. Kuehner ◽

...

Keyword(s):

Angular Distribution ◽

Band Structure ◽

Linear Polarization ◽

Negative Parity ◽

Mixing Ratios ◽

Decay Branch ◽

Nilsson Model ◽

Γ Rays ◽

Model Evidence ◽

Γ Ray

The 18O(α,nγ) reaction at α-particle bombarding energies of 5.2 and 6.1 MeV was used to study the levels in 21Ne below 4 MeV excitation. A combination of γ-ray angular distribution and linear polarization measurements using a single crystal Ge(Li) polarimeter confirmed the spins and parities of the 1747 and 2867 keV states to be 7/2+ and 9/2+ respectively and assigned negative parity to the J = 3/2 level at 3663 keV and J = 5/2 level at 3886 keV. The state at 3735 keV was shown to have Jπ = 5/2+. Values of the multipole mixing ratios of γ rays deexciting these states were found to be consistent with previous measurements. A γ–γ coincidence experiment revealed the existence of a (1.8 ± 0.7)% decay branch of the 3886 keV level to the 2790 keV level. The results are interpreted in terms of the Nilsson model. Evidence for the existence of a Kπ = 1/2− band based on a hole in the 1p1/2 shell is given.

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Study of Low-Lying Levels in 37Ar

Canadian Journal of Physics ◽

10.1139/p72-163 ◽

1972 ◽

Vol 50 (11) ◽

pp. 1182-1194 ◽

Cited By ~ 11

Author(s):

P. Taras ◽

A. Turcotte ◽

R. Vaillancourt

Keyword(s):

Angular Distribution ◽

Gamma Rays ◽

Linear Polarization ◽

Ground State ◽

Solar Neutrino ◽

Gamma Ray ◽

Capture Rate ◽

Mixing Ratio ◽

Excitation Energies ◽

Decay Gamma

The properties of the first five excited levels in 37Ar were investigated via the 37Cl(p,n)37Ar reaction at Ep = 3.98, 4.17, 4.38, and 4.81 MeV and via the 34S(α,n)37Ar reaction at Eα = 8.00, 8.50, and 8.60 MeV. The following excitation energies were obtained: Ex = 1409.7 ± 0.4, 1611.5 ± 0.4, 2217.8 ± 0.8, 2491.4 ± 0.8, and 2797.0 ± 0.8 keV. These levels were found to decay almost entirely to the ground state. The angular distribution and the linear polarization of the decay gamma rays of these levels were measured. From these measurements definite spin–parity assignments as well as values of the mixing ratio of the ground state gamma-ray transitions were obtained. These are: Ex(Jπ, δ) = 1612 ([Formula: see text], +0.11 ± 0.02), 2218 ([Formula: see text], 0.0 ± 0.02), 2491 ([Formula: see text]), and 2797 ([Formula: see text], −0.16 ± 0.03 or +8.0 ± 1.5, the value of −0.16 being more probable). The measurements were also consistent with a spin of [Formula: see text] for the 1410 keV level. The results are compared with a recent shell-model calculation and are discussed in the context of the solar neutrino capture rate in 37Cl.

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Experimental investigation and modelling of light scattering in a-Si:H solar cells deposited on glass/ZnO:Al substrates

MRS Proceedings ◽

10.1557/proc-715-a13.3 ◽

2002 ◽

Vol 715 ◽

Cited By ~ 3

Author(s):

J. Krc ◽

M. Zeman ◽

O. Kluth ◽

F. Smole ◽

M. Topic

Keyword(s):

Surface Roughness ◽

Experimental Investigation ◽

Solar Cells ◽

Angular Distribution ◽

Light Scattering ◽

Optical Model ◽

Distribution Functions ◽

Interface Roughness ◽

Scattering Parameters ◽

Good Agreement

AbstractThe descriptive scattering parameters, haze and angular distribution functions of textured ZnO:Al transparent conductive oxides with different surface roughness are measured. An approach to determine the scattering parameters of all internal interfaces in p-i-n a-Si:H solar cells deposited on the glass/ZnO:Al substrates is presented. Using the determined scattering parameters as the input parameters of the optical model, a good agreement between the measured and simulated quantum efficiencies of the p-i-n a-Si:H solar cells with different interface roughness is achieved.

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Measurement of growth rates for single crystals and pressed tablets of CuSO4.5 H2O on a rotating disc

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19892951 ◽

1989 ◽

Vol 54 (11) ◽

pp. 2951-2961 ◽

Cited By ~ 2

Author(s):

Miloslav Karel ◽

Jaroslav Nývlt

Keyword(s):

Growth Rate ◽

Single Crystal ◽

Single Crystals ◽

Growth Rates ◽

Diffusion Coefficients ◽

Preferred Orientation ◽

Rotating Disc ◽

Dissolution Rates ◽

Rates Of Growth ◽

Good Agreement

Measured growth and dissolution rates of single crystals and tablets were used to calculate the overall linear rates of growth and dissolution of CuSO4.5 H2O crystals. The growth rate for the tablet is by 20% higher than that calculated for the single crystal. It has been concluded that this difference is due to a preferred orientation of crystal faces on the tablet surface. Calculated diffusion coefficients and thicknesses of the diffusion and hydrodynamic layers in the vicinity of the growing or dissolving crystal are in good agreement with published values.

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