A test of a model t-matrix for direct reaction inelastic scattering

A symmetry property of the exact T matrix for the inelastic scattering of particles with arbitrary spin is derived, in the adiabatic limit, using time reversal invariance properties of the elastic scattering amplitude and neglecting interaction terms that involve spins or velocities of the target nucleons. The symmetry property is used to show the equality of the generalized polarization and asymmetry tensors for inelastic scattering and to derive the symmetry properties, with respect to the adiabatic recoil axis, of the angular correlation function and the circular polarization of the deexcitation gamma rays. It is also shown that the nuclear excited state is aligned along the axis normal to the scattering plane. A brief discussion of the symmetry properties of the adiabatic DWBA amplitude is given. When interaction terms involving spins or velocities of the target nucleons are taken into account, it is shown that the inelastic scattering T matrix can be divided into two parts; one that satisfies the above-mentioned symmetry relation, and a second part which has a different symmetry.

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Direct Reaction Inelastic Scattering to the 2? State of 16O Via a Nonlocal Interaction

Australian Journal of Physics ◽

10.1071/ph730315 ◽

1973 ◽

Vol 26 (3) ◽

pp. 315 ◽

Cited By ~ 1

Author(s):

F Ruzzene ◽

K Amos

Keyword(s):

Inelastic Scattering ◽

Cross Sections ◽

Born Approximation ◽

Measured Data ◽

Nonlocal Interaction ◽

Direct Reaction ◽

Target Nucleon ◽

Proton Inelastic Scattering ◽

Plane Wave Born Approximation ◽

Mev Protons

A study is made of the effects of a purely nonlocal representation of the reaction mechanism in inelastic scattering. In particular, the inelastic scattering of 30 MeV protons and 65 MeV IX-particles leading to the 2- state of 8�88 MeV excitation in 160 are considered. The reaction mechanisms are represented by separable interactions between the projectile and target nucleon, and a simple spectroscopy for 160 is used in the plane wave Born approximation. The derived cross sections are compared with other calculations and the measured data. The asymmetry in proton inelastic scattering is also discussed.

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Off-shell resonances in coupled channel problems

Canadian Journal of Physics ◽

10.1139/p79-112 ◽

1979 ◽

Vol 57 (6) ◽

pp. 801-808 ◽

Cited By ~ 1

Author(s):

G. Pantis

Keyword(s):

Nuclear Reactions ◽

Bound State ◽

Direct Reaction ◽

Background Term ◽

Separable Potentials ◽

State Behaviour ◽

Square Well ◽

T Matrix ◽

Coupled Channel ◽

Channel Theory

The coupled channel theory of nuclear reactions is extended off the energy shell so that the T-matrix can be constructed to include both the direct reaction contribution and the contribution from the off-shell background scattering. This has been shown to be important for (d,p) stripping reactions to unbound states. Three soluble two-channel models with square well, δ-function, and separable potentials, are presented and the resonance and bound state behaviour is discussed in some numerical detail. The importance of the off-shell background term is also studied.

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Nucleon-induced inelastic scattering with statistical strength functions and the ECIS direct reaction code

The European Physical Journal A ◽

10.1140/epja/s10050-021-00497-6 ◽

2021 ◽

Vol 57 (6) ◽

Author(s):

E. V. Chimanski ◽

B. V. Carlson

Keyword(s):

Inelastic Scattering ◽

Direct Reaction ◽

Statistical Strength ◽

Strength Functions

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ON THE STICKING MECHANISM IN PRESENCE OF INELASTIC SCATTERING AND SELECTIVE ADSORPTION RESONANCES

International Journal of Modern Physics B ◽

10.1142/s0217979299001521 ◽

1999 ◽

Vol 13 (12) ◽

pp. 1477-1487

Author(s):

G. DUTTAMUDI ◽

S. K. ROY

Keyword(s):

Inelastic Scattering ◽

Temperature Variation ◽

Born Approximation ◽

Selective Adsorption ◽

Bound State ◽

Distorted Wave ◽

Distorted Wave Born Approximation ◽

T Matrix ◽

Solid Argon ◽

Sticking Coefficients

The sticking coefficients of He 4 on graphite and solid argon surfaces are calculated in presence of bound state resonances. It is observed that the over-counting of the scattering events which make the sticking coefficients greater than unity in these systems under usual distorted wave Born approximation (DWBA), can be removed by considering the exact T-matrix in presence of bound state resonances. This also gives rise to interesting results on temperature variation of sticking coefficients.

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Analysis of STEM micrographs of thick objects

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081395 ◽

1978 ◽

Vol 36 (2) ◽

pp. 106-107

Author(s):

S. Golladay

Keyword(s):

Inelastic Scattering ◽

Multiple Scattering ◽

Mass Distribution ◽

Cross Sections ◽

Phase Contrast ◽

Image Point ◽

Contrast Effects ◽

Total Cross Sections ◽

Elastic And Inelastic Scattering

The theory of multiple scattering has been worked out by Groves and comparisons have been made between predicted and observed signals for thick specimens observed in a STEM under conditions where phase contrast effects are unimportant. Independent measurements of the collection efficiencies of the two STEM detectors, calculations of the ratio σe/σi = R, where σe, σi are the total cross sections for elastic and inelastic scattering respectively, and a model of the unknown mass distribution are needed for these comparisons. In this paper an extension of this work will be described which allows the determination of the required efficiencies, R, and the unknown mass distribution from the data without additional measurements or models. Essential to the analysis is the fact that in a STEM two or more signal measurements can be made simultaneously at each image point.

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Temperature Dependence of the Critical Electron Dose for Fatty Acid Monolayers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053188 ◽

1982 ◽

Vol 40 ◽

pp. 78-79

Author(s):

Kenneth H. Downing ◽

Robert M. Glaeser

Keyword(s):

Electron Beam ◽

Fatty Acid ◽

Inelastic Scattering ◽

Temperature Dependence ◽

Structural Damage ◽

Direct Result ◽

Second Step ◽

Strong Temperature Dependence ◽

Electron Dose ◽

Covalent Bonds

The structural damage of molecules irradiated by electrons is generally considered to occur in two steps. The direct result of inelastic scattering events is the disruption of covalent bonds. Following changes in bond structure, movement of the constituent atoms produces permanent distortions of the molecules. Since at least the second step should show a strong temperature dependence, it was to be expected that cooling a specimen should extend its lifetime in the electron beam. This result has been found in a large number of experiments, but the degree to which cooling the specimen enhances its resistance to radiation damage has been found to vary widely with specimen types.

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The Resolution and Contrast in Biological Sections Determined by Inelastic and Elastic Scattering

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071569 ◽

1973 ◽

Vol 31 ◽

pp. 224-225

Author(s):

D. L. Misell

Keyword(s):

Electron Microscopy ◽

Adverse Effect ◽

Elastic Scattering ◽

Inelastic Scattering ◽

Amorphous Carbon ◽

Polymeric Materials ◽

Chromatic Aberration ◽

Image Resolution ◽

Quantitative Estimates ◽

Elastic Ratio

In the electron microscopy of biological sections the adverse effect of chromatic aberration on image resolution is well known. In this paper calculations are presented for the inelastic and elastic image intensities using a wave-optical formulation. Quantitative estimates of the deterioration in image resolution as a result of chromatic aberration are presented as an alternative to geometric calculations. The predominance of inelastic scattering in the unstained biological and polymeric materials is shown by the inelastic to elastic ratio, I/E, within an objective aperture of 0.005 rad for amorphous carbon of a thickness, t=50nm, typical of biological sections; E=200keV, I/E=16.

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