Inelastic Scattering from Surface Zero-Sound Modes: A Model Calculation

We analyze the α inelastic scattering on 12 C by the coupled-channel calculation based on the folding model potential. We show that the ordinary folding model calculation tends to overestimate the [Formula: see text] inelastic angular distribution, and that this discrepancy is not due to the 3α breakup effect. In order to resolve this problem, we propose a folding procedure considering the well-developed 3α cluster structure of [Formula: see text].

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Low-Lying Structure and Inelastic Scattering of Cu Isotopes in a Unified Model

Canadian Journal of Physics ◽

10.1139/p72-220 ◽

1972 ◽

Vol 50 (14) ◽

pp. 1630-1643 ◽

Cited By ~ 24

Author(s):

B. Castel ◽

I. P. Johnstone ◽

B. P. Singh ◽

K. W. C. Stewart

Keyword(s):

Inelastic Scattering ◽

Shell Model ◽

Model Calculation ◽

Cross Sections ◽

Experimental Spectrum ◽

Quasi Particle ◽

The Core ◽

Anharmonic Vibrations ◽

Cu Isotopes ◽

Scattering Cross Sections

The odd-Cu isotopes are examined in a model which couples quasi-particle states to anharmonic vibrations of neighboring Ni cores. The f7/2, f5/2, p3/2, and p1/2 orbitals are available and the core properties are taken directly from the experimental spectrum of the Ni isotopes. The results are compared with experimental estimates as well as with a recent shell model calculation. The inelastic scattering cross sections for protons on 65Cu are also discussed within the framework of this model.

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Coupling of rayleigh-like waves with zero-sound modes in normal3He

Journal of Low Temperature Physics ◽

10.1007/bf00681657 ◽

1985 ◽

Vol 60 (1-2) ◽

pp. 133-147 ◽

Cited By ~ 3

Author(s):

S. A. Bogacz ◽

J. B. Ketterson

Keyword(s):

Zero Sound ◽

Sound Modes

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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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Resolving Crystallites in Zirconium Oxide Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100062610 ◽

1969 ◽

Vol 27 ◽

pp. 140-141

Author(s):

R.A. Ploc

Keyword(s):

Electron Microscope ◽

Inelastic Scattering ◽

Zirconium Oxide ◽

Oxide Films ◽

Optic Axis ◽

Objective Lens ◽

Microscope Objective ◽

Linear Optic ◽

A Current ◽

Microscope Objective Lens

The optic axis of an electron microscope objective lens is usually assumed to be straight and co-linear with the mechanical center. No reason exists to assume such perfection and, indeed, simple reasoning suggests that it is a complicated curve. A current centered objective lens with a non-linear optic axis when used in conjunction with other lenses, leads to serious image errors if the nature of the specimen is such as to produce intense inelastic scattering.

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An Environmental Wet Cell For High Voltage Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070539 ◽

1973 ◽

Vol 31 ◽

pp. 18-19

Author(s):

N.J. Tighe ◽

H.M. Flower ◽

P.R. Swann

Keyword(s):

Electron Microscopy ◽

High Temperature ◽

Image Quality ◽

Inelastic Scattering ◽

High Voltage ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Environmental Cell ◽

Water Saturated ◽

High Temperature Gas

A differentially pumped environmental cell has been developed for use in the AEI EM7 million volt microscope. In the initial version the column of gas traversed by the beam was 5.5mm. This permited inclusion of a tilting hot stage in the cell for investigating high temperature gas-specimen reactions. In order to examine specimens in the wet state it was found that a pressure of approximately 400 torr of water saturated helium was needed around the specimen to prevent dehydration. Inelastic scattering by the water resulted in a sharp loss of image quality. Therefore a modified cell with an ‘airgap’ of only 1.5mm has been constructed. The shorter electron path through the gas permits examination of specimens at the necessary pressure of moist helium; the specimen can still be tilted about the side entry rod axis by ±7°C to obtain stereopairs.

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The effect of temperature on high-resolution TEM image contrast

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139573 ◽

1995 ◽

Vol 53 ◽

pp. 640-641

Author(s):

T. Geipel ◽

W. Mader ◽

P. Pirouz

Keyword(s):

Form Factor ◽

Inelastic Scattering ◽

Accurate Method ◽

Waller Factor ◽

Effect Of Temperature ◽

Specimen Thickness ◽

Influence Of Temperature ◽

Debye Waller Factor ◽

Influence Of Temperature On ◽

Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

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