335 Optimization of the mean energy of the incident electron beam for MCTP by removing the beam-modifying filters from the linac head

2005 ◽  
Vol 76 ◽  
pp. S152
Author(s):  
B. De Smedt ◽  
N. Reynaert ◽  
F. Flachet ◽  
M. Coghe ◽  
L. Paelinck ◽  
...  
Keyword(s):  
Electron Beam ◽  
Incident Electron ◽  
Incident Electron Beam ◽  
The Mean

The influence of supporting grid bars on the temperatore increase of a thin fiim subjected to electron irradiation

1990 ◽  
Vol 48 (4) ◽  
pp. 814-815
Author(s):  
A.E. Curzon
Keyword(s):  
Electron Beam ◽  
Cross Section ◽  
Circular Cross Section ◽  
Incident Electron ◽  
Inert Gases ◽  
Main Beam ◽  
Sources And Sinks ◽  
Incident Electron Beam ◽  
Transmission Electron ◽  
Limiting Case

The heating effect of an incident electron beam may cause a material to be radiation-sensitive. For example, the adsorption behaviour of inert gases on graphite observed in a transmission electron microscope depends critically on the temperature of the substrate. Early consideration of beam heating dealt with a circular film illuminated at the centre by an electron beam of circular cross-section. In practice, however, the film is often supported across a square aperture and is not centrally illuminated. It has recently been shown that the method of images may be used to solve the problem of the heating of a square film of thermal conductivity k by a beam whose cross-section is entirely within the film. This solution has the advantage that it applies regardless of where the incident electron beam strikes the film. The general solution involves an infinite sum over a two dimensional lattice of heat sources and sinks. Though the sum is readily evaluated by means of a computer, it is helpful to consider a particular limiting case which is readily understood in terms of three images and the main beam. This case is illustrated in Figure 1.

Artifacts introduced into AES analysis by the incident electron beam

Vacuum ◽  
1976 ◽  
Vol 26 (10-11) ◽  
pp. 421
Author(s):  
J.P. Coad ◽  
M. Gettings ◽  
J.C. Rivière
Keyword(s):  
Electron Beam ◽  
Incident Electron ◽  
Incident Electron Beam

scholarly journals Absolute Intensities of Characteristic Ka Radiation from an Inclined Copper Target

1964 ◽  
Vol 17 (1) ◽  
pp. 45
Author(s):  
V Metchnik
Keyword(s):  
Electron Beam ◽  
Scintillation Counter ◽  
Normal Incidence ◽  
Absolute Intensity ◽  
Incident Electron ◽  
Experimental Results ◽  
Copper Target ◽  
Absolute Intensities ◽  
Incident Electron Beam ◽  
The Absolute

Experimental results are given for the measurements of the absolute intensity of characteristic Ka radiation from a thick copper target when the normal to the target is inclined to the incident electron beam at an angle (I equal to 20�, 30�, 40�, and 50�. These measurements cover a range of electron energies between 20 and 50 kV, and take�off angles q, ranging from 1� to 50�. A comparison is made with the emission at normal incidence. The copper Ka radiation was isolated by means of balanced nickel and iron filters, and the intensity mllasurements were made with a scintillation counter with NaI(TI) crystal

Conventional methods of Lorentz microscopy

1990 ◽  
Vol 48 (4) ◽  
pp. 756-757
Author(s):  
H.Roy Geiss
Keyword(s):  
Thin Films ◽  
Electron Beam ◽  
Vector Potential ◽  
Magnetic Thin Films ◽  
Incident Electron ◽  
Objective Lens ◽  
Zero Field ◽  
Magnetic Vector Potential ◽  
Lorentz Microscopy ◽  
Incident Electron Beam

Lorentz electron microscopy has been used to study magnetic domain/domain wall structures in thin films since 1959. Initially the contrast was described in terms of the classical Lorentz deflection of the incident electron beam. As a result Lorentz microscopy has become the general designation given to any of the techniques used to study the magnetic structure with electron beams. However, when sufficiently weak interactions are considered, a more rigorous quantum-mechanical description of the electron-specimen is required. It thus becomes necessary to consider the basis of magnetic imaging as following from the interaction between the magnetic vector potential of the specimen and the incident electron beam. This interaction results in a phase change of the propagating electron beam which is proportional to the path integral of the vector potential. Thus Lorentz microscopy, in reality, is simply phase contrast microscopy for a special class of objects.For many of the magnetic thin films investigated the coercivity of the film is so low that it must be in a nearly zero field environment in order to retain the domain structure. In order to achieve this condition experimentally, the objective lens is usually turned off and the diffraction lens is used as the image forming lens.

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