scholarly journals Absolute cross section measurements for the scattering of low- and intermediate-energy electrons from PF3. I. Elastic scattering

2017 ◽  
Vol 147 (22) ◽  
pp. 224308 ◽  
Author(s):  
N. Hishiyama ◽  
M. Hoshino ◽  
F. Blanco ◽  
G. García ◽  
H. Tanaka
Keyword(s):  
Elastic Scattering ◽  
Cross Section ◽  
Intermediate Energy ◽  
Absolute Cross Section

scholarly journals New and Old Measurements of Electron Scattering in Atomic Hydrogen

1998 ◽  
Vol 51 (4) ◽  
pp. 633 ◽  
Author(s):  
J. F. Williams
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Atomic Hydrogen ◽  
Intermediate Energy ◽  
Absolute Calibration ◽  
Absolute Cross Section ◽  
Close Coupling ◽  
R Matrix ◽  
Correlation Parameters

A critical look is made of discrepancies and agreements between new and old measurements and theories for elastic and n = 2 excitation of atomic hydrogen by electron impact, mainly at 16·5, 54 and 100 eV. A discussion of earlier work indicates the contributions of Weigold and colleagues. The diffculties of observing and modelling small scattered fluxes at backward scattering angles and of making absolute cross section calibrations are noted. New measurements of elastic scattering at 16·5 eV confirm earlier measured angular distributions. An absolute calibration of the differential cross section at 16·5 eV gives agreement within one standard deviation with intermediate energy R-matrix and multi-pseudostate close coupling values. At 16·5 eV, measurements of the separate 2s and 2p differential cross sections and the lambda, R and I correlation parameters again support the values from those theories.

Elastic scattering of intermediate-energy positrons and electrons by alkali atoms

1982 ◽  
Vol 60 (4) ◽  
pp. 601-604 ◽  
Author(s):  
J. M. Wadehra
Keyword(s):  
Wave Function ◽  
Elastic Scattering ◽  
Cross Section ◽  
Born Approximation ◽  
Intermediate Energy ◽  
Target Atom ◽  
Slater Type ◽  
Hartree Fock ◽  
Static Interaction ◽  
Alkali Atoms

In this paper we present the total elastic scattering cross section for collisions of intermediate energy (500–1000 eV) positrons and electrons by alkali atoms (Li, Na, K, Rb). Calculations are done by using the first Born approximation with polarization plus static interaction. The static interaction is obtained by using a Hartree–Fock–Slater type wave function for the target atom and the polarization interaction is modeled by using a pseudopotential.

Elastic Scattering in Electron Microscopy

1973 ◽  
Vol 31 ◽  
pp. 252-253
Author(s):  
J. Langmore ◽  
M. Isaacson ◽  
J. Wall ◽  
A. V. Crewe
Keyword(s):  
Electron Microscopy ◽  
Elastic Scattering ◽  
Cross Section ◽  
Quantum Noise ◽  
Dark Field ◽  
Elastic Cross Section ◽  
Biological Molecules ◽  
Dark Field Microscopy ◽  
Field Systems ◽  
Effects Of Radiation

High resolution dark field microscopy is becoming an important tool for the investigation of unstained and specifically stained biological molecules. Of primary consideration to the microscopist is the interpretation of image Intensities and the effects of radiation damage to the specimen. Ignoring inelastic scattering, the image intensity is directly related to the collected elastic scattering cross section, σɳ, which is the product of the total elastic cross section, σ and the eficiency of the microscope system at imaging these electrons, η. The number of potentially bond damaging events resulting from the beam exposure required to reduce the effect of quantum noise in the image to a given level is proportional to 1/η. We wish to compare η in three dark field systems.

Absolute inner-shell cross section determination for EELS analysis

1988 ◽  
Vol 46 ◽  
pp. 534-535
Author(s):  
P.A. Crozier
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Absolute Cross Section ◽  
Specimen Thickness ◽  
Mass Thickness ◽  
Scattering Cross ◽  
Before And After ◽  
Estimated Error ◽  
Scattering Cross Sections ◽  
Electron Microscopist

Absolute inelastic scattering cross sections or mean free paths are often used in EELS analysis for determining elemental concentrations and specimen thickness. In most instances, theoretical values must be used because there have been few attempts to determine experimental scattering cross sections from solids under the conditions of interest to electron microscopist. In addition to providing data for spectral quantitation, absolute cross section measurements yields useful information on many of the approximations which are frequently involved in EELS analysis procedures. In this paper, experimental cross sections are presented for some inner-shell edges of Al, Cu, Ag and Au.Uniform thin films of the previously mentioned materials were prepared by vacuum evaporation onto microscope cover slips. The cover slips were weighed before and after evaporation to determine the mass thickness of the films. The estimated error in this method of determining mass thickness was ±7 x 107g/cm2. The films were floated off in water and mounted on Cu grids.

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