Angular distributions of recoil products from some reactions induced in 65Cu and 197Au by protons of energy 30–85 MeV

1968 ◽  
Vol 46 (22) ◽  
pp. 3551-3563 ◽  
Author(s):  
M. K. Dewanjee ◽  
G. B. Saha ◽  
L. Yaffe
Keyword(s):  
Angular Distribution ◽  
Inelastic Scattering ◽  
Center Of Mass ◽  
Interaction Mechanism ◽  
Direct Interaction ◽  
Low Energy ◽  
Angular Distributions ◽  
Approximate Symmetry ◽  
Mass System ◽  
Model Calculations

Angular distributions of products formed in the reactions 65Cu(p,pn)64Cu, 197Au(p,pn)I96Au, and 197Au(p,p3n)194Au in the range of proton energy 30–85 MeV were studied. The angular distribution results of 64Cu and 196Au show forward peaking at low energy and sidewise peaking at higher energies. Approximate symmetry about 90° was observed for the angular distribution of 194Au in the center-of-mass system. The experimental results have been compared with (a) Monte Carlo evaporation calculations, (b) cascade–evaporation calculations at 85 MeV for 64Cu, and (c) inelastic scattering plus evaporation calculations.Good agreement was obtained with statistical theory calculations at low energy and inelastic scattering model calculations at higher energies. The comparisons indicate that the reactions proceed by the compound nucleus mechanism at lower energies and the direct interaction mechanism predominates at higher energies.

Average recoil ranges of 64Cu and 196Au produced by protons of 20–85 MeV energy in 65Cu and 197Au

1968 ◽  
Vol 46 (20) ◽  
pp. 3157-3170
Author(s):  
M. K. Dewanjee ◽  
G. B. Saha ◽  
L. Yaffe
Keyword(s):  
Statistical Theory ◽  
Inelastic Scattering ◽  
Reasonable Agreement ◽  
Interaction Mechanism ◽  
Direct Interaction ◽  
Thick Target ◽  
Model Calculations ◽  
Projected Range ◽  
Low Energies ◽  
The Average Range

Thick-target recoil experiments were performed to study (p,pn) reactions induced in 65Cu and 197Au in the energy range of 20–85 MeV and the average ranges projected in the forward, backward, and perpendicular directions were determined. Recoil parameters have been calculated to show approximately the amount of energy transfer and their energy dependence. The average range results have been compared with statistical theory, cascade–evaporation (85 MeV only), and inelastic scattering model calculations. The statistical calculations show reasonable agreement up to 30–40 MeV. However, the calculated projected range values, based on the cascade–evaporation and the inelastic scattering models, are consistently lower than the measured values. The analyses of the projected range values support the prevalent view that at low energies (~ 30–35 MeV), the compound nucleus mechanism is predominant and at higher energies, the direct interaction mechanism makes a major contribution.

THE ANGULAR DISTRIBUTION OF PHOTOFISSION FRAGMENTS

1959 ◽  
Vol 37 (12) ◽  
pp. 1418-1437 ◽  
Author(s):  
A. P. Baerg ◽  
R. M. Bartholomew ◽  
F. Brown ◽  
L. Katz ◽  
S. B. Kowalski
Keyword(s):  
Angular Distribution ◽  
Low Energy ◽  
Photon Beam ◽  
Angular Distributions ◽  
Bremsstrahlung Energy ◽  
Isotropic Distribution ◽  
Degree Of Anisotropy ◽  
Maximum Bremsstrahlung Energy

Angular distributions of photofission fragments relative to the photon beam have been measured as a function of maximum bremsstrahlung energy in the range 6–20 Mev. The nuclides U-233, U-235, Np-237, Pu-239, and Am-241 give an isotropic distribution at all energies studied. The nuclides Th-232, U-234, U-236, U-238, and Pu-240 give anisotropic distributions which can be described by an equation of the form W(θ) = 1 + α sin2 θ where θ is the angle between fragment and beam. The degree of anisotropy is large at low energy and falls rapidly as the energy is increased. At a given energy Th-232 has the greatest degree of anisotropy and Pu-240 the least.

scholarly journals p-Wave Strength in the Low-energy 7Li(p,?0)8Be Cross Section

1995 ◽  
Vol 48 (5) ◽  
pp. 813 ◽  
Author(s):  
FC Barker
Keyword(s):  
Angular Distribution ◽  
Shell Model ◽  
Cross Section ◽  
Low Energy ◽  
P Wave ◽  
Model Calculations ◽  
Energy Data

Recent fits to low-energy 7Li(p, "Yo)8Be angular distribution and analysing power data suggested a large p-wave strength. It is shown that acceptable fits to the data can be obtained by attributing the p-wave Ml contributions to the tails of the 17 �64 and 18 �15 MeV 1+ levels of 8Be, with p-wave strengths much less than those obtained previously, but only if some of the spectroscopic amplitudes have signs opposite to those suggested by shell model calculations and/or a fit to higher-energy data.

scholarly journals The inelastic scattering of slow electrons in gases.—IV

1933 ◽  
Vol 142 (847) ◽  
pp. 647-658 ◽  
Keyword(s):  
Angular Distribution ◽  
Inelastic Scattering ◽  
Incident Electron ◽  
Angular Distributions ◽  
Mercury Vapour ◽  
Preliminary Results ◽  
Excitation Potential ◽  
Discrete Amount ◽  
Slow Electrons ◽  
Diffraction Effects

Recent investigations have shown that the inelastic scattering of electrons in gases exhibits some very interesting phenomena. In previous papas we have described the angular distribution of the scattering of electrons which have lost a discrete amount of energy. Papers I and II described preliminary results which established the existence of diffraction effects at large angles in a number of gases. In Paper III the measurements were carried out over a range of velocities lower than those previously studied, results being obtained for incident electron energies down to within a few volts of the excitation potential. angular distributions were obtained for the inelastic scattering of electrons in hydrogen, helium, and argon between the angles 10° and 155°. The present paper describes the extension of the measurements to methane, nitrogen, neon and mercury vapour.

A STUDY OF THE Be9(He3, n)C11 REACTION

1963 ◽  
Vol 41 (7) ◽  
pp. 1036-1046 ◽  
Author(s):  
L. van der Zwan ◽  
A. T. Stewart ◽  
J. Y. Park ◽  
E. Merzbacher
Keyword(s):  
Compound Nucleus ◽  
Cross Sections ◽  
Interaction Mechanism ◽  
Direct Interaction ◽  
Particle Energy ◽  
Energy Spectra ◽  
Angular Distributions ◽  
Proton Recoil ◽  
The Cross ◽  
Photographic Emulsions

The energy spectra and angular distributions of the emergent neutrons from the Be9(He3, n)C11 reaction have been obtained for an incident He3-particle energy of 2 Mev with the technique of observing proton recoil in photographic emulsions. The cross sections were normalized to Be9(He3, p)B11 data observed simultaneously at 90° to the beam. The lack of similarity in the (He3, n) and (He3, p) mirror reactions to some residual states suggests a direct interaction mechanism rather than compound nucleus. An attempt to analyze some of the data in terms of double particle stripping has been made.

THE REACTION D(p, γ)He3 BELOW 50 KEV

1963 ◽  
Vol 41 (5) ◽  
pp. 724-736 ◽  
Author(s):  
G. M. Griffiths ◽  
M. Lal ◽  
C. D. Scarfe
Keyword(s):  
Angular Distribution ◽  
Cross Sections ◽  
Center Of Mass ◽  
P Wave ◽  
Laboratory System ◽  
S Wave ◽  
Mass System ◽  
S Factor ◽  
Low Energies ◽  
Γ Rays

The yield and angular distribution of the γ rays from the reaction D(p, γ) He3 have been measured with thick heavy-ice targets in the energy range from 24 kev to 48 kev. Assuming a simplified energy dependence the results have been analyzed to give cross sections for p-wave and s-wave capture. At 25 kev in the laboratory system, the cross sections are[Formula: see text]The astrophysical S-factors in the center-of-mass system below 40 kev have been found to be[Formula: see text]for E in center-of-mass kilovolts and[Formula: see text]independent of energy giving a total S-factor for low energies[Formula: see text]with E in center-of-mass kilovolts.

THE SCATTERING OF PROTONS ON 7Li, 9Be, AND 12C AT 100 MEV

1966 ◽  
Vol 44 (12) ◽  
pp. 2961-2971 ◽  
Author(s):  
S. K. Mark ◽  
P. M. Portner ◽  
R. B. Moore
Keyword(s):  
Angular Distribution ◽  
Inelastic Scattering ◽  
Cross Sections ◽  
Differential Cross ◽  
Target Nucleus ◽  
Energy Region ◽  
Angular Distributions ◽  
Angular Range ◽  
Existing Data ◽  
Octupole Excitation

Elastic and inelastic scattering of protons on 7Li, 9Be, and 12C have been studied, using the 100-MeV proton beam from the McGill synchrocyclotron. Differential cross sections for the various groups of scattered protons were measured over an angular range of 5° to 90° (lab). For proton groups resulting from a quadrupole excitation in the target nucleus, the angular distribution was found to increase at scattering angles less than 10°. Angular distributions corresponding to an octupole excitation were observed to decrease at small angles. The results have been compared with existing data in this energy region.

Scattering of α-particles and 3He on 16O nuclei and its excitation mechanism at energies near 50MeV

2017 ◽  
Vol 26 (04) ◽  
pp. 1750018 ◽  
Author(s):  
N. Burtebayev ◽  
A. Duysebayev ◽  
B. A. Duysebayev ◽  
J. Burtebayeva ◽  
M. Nassurlla ◽  
...  
Keyword(s):  
Inelastic Scattering ◽  
Good Description ◽  
Center Of Mass ◽  
Angular Distributions ◽  
Octupole Deformation ◽  
Coupled Channels ◽  
Cluster Transfer ◽  
Microscopic Models ◽  
Nuclear Rainbow ◽  
Α Particles

Elastic and inelastic scattering of [Formula: see text]-particles at 48.1[Formula: see text]MeV and 3He at 60[Formula: see text]MeV on [Formula: see text]O nuclei has been measured with excitation of states at 6.05 (0[Formula: see text])–6.13 (3[Formula: see text])[Formula: see text]MeV, 6.92 (2[Formula: see text])–7.12 (1[Formula: see text])[Formula: see text]MeV and 8.87 (2[Formula: see text])[Formula: see text]MeV. The center-of-mass beam momenta are the same for these two strongly absorbed particles. Analysis of angular distributions was performed in the frameworks of the optical model, the coupled channels method and the Distorted Wave Born Approximation (DWBA). A good description of experimental data was obtained over the full angular range without taking into account the spin-orbit interaction and the cluster transfer mechanism with real potentials that have volume integrals of about 400[Formula: see text]MeV fm3. Collective and microscopic models were used in the analysis of the inelastic scattering. The values of the octupole deformation lengths were extracted. It is shown that nuclear rainbow effects appear not only in the elastic, but also in the inelastic scattering with excitation of the 3[Formula: see text] state of [Formula: see text]O.

scholarly journals NEW RESULTS ON THE pd→3Heη PRODUCTION NEAR THRESHOLD

2005 ◽  
Vol 20 (02n03) ◽  
pp. 643-645 ◽  
Author(s):  
H.-H. ADAM ◽  
A. KHOUKAZ ◽  
N. LANG ◽  
T. LISTER ◽  
R. SANTO ◽  
...  
Keyword(s):  
Cross Sections ◽  
Differential Cross ◽  
Final State Interaction ◽  
Center Of Mass ◽  
Meson Production ◽  
Angular Distributions ◽  
Final State ◽  
Mass System ◽  
Total Cross Sections ◽  
Model Predictions

Measurements on the η meson production in proton-deuteron collisions have been performed using the COSY-11 facility at COSY (Jülich). Here we present preliminary results on total and differential cross sections for the pd→3 He η reaction at five excess energies between Q=5.1 and Q=40.6 MeV. The obtained angular distributions for the emitted η mesons in the center of mass system expose a transition from an almost isotropic emission to a highly anisotropic distribution. The extracted total cross sections support a strong η-3 He final state interaction and will be compared with model predictions.

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