Design parameters of an electrostatic analyser for recording the energy and angular distribution of positrons and electrons simultaneously

1991 ◽  
Vol 2 (5) ◽  
pp. 448-454 ◽  
Author(s):  
A Kover
1998 ◽  
Vol 5 (3) ◽  
pp. 569-571 ◽  
Author(s):  
V. R. Dhanak ◽  
A. G. Shard ◽  
C. A. Muryn ◽  
P. L. Wincott ◽  
G. Thornton

The performance of a recently commissioned beamline, designated BL4.1, at the SRS, Daresbury Laboratory, is described. This beamline covers the energy range 15 ≥ hυ ≥ 200 eV, using a spherical grating monochromator, and is equipped with a UHV surface-science endstation containing a Scienta SES200 and an HA54 angle-resolving electron-energy analyser. Design parameters and optical specifications are tabulated. Monochromator resolution has been determined by measuring the Fermi edge of a Pt foil cooled to 40 K and these values are compared with the calculated resolution. The flux delivered to the endstation has been measured directly using a calibrated photodiode. The performance of the beamline is further illustrated by reference to a study of the angular distribution of photoemitted intensity from a band-gap state on a TiO2(110) 1 × 2 surface.


Author(s):  
Ryuichi Shimizu ◽  
Ze-Jun Ding

Monte Carlo simulation has been becoming most powerful tool to describe the electron scattering in solids, leading to more comprehensive understanding of the complicated mechanism of generation of various types of signals for microbeam analysis.The present paper proposes a practical model for the Monte Carlo simulation of scattering processes of a penetrating electron and the generation of the slow secondaries in solids. The model is based on the combined use of Gryzinski’s inner-shell electron excitation function and the dielectric function for taking into account the valence electron contribution in inelastic scattering processes, while the cross-sections derived by partial wave expansion method are used for describing elastic scattering processes. An improvement of the use of this elastic scattering cross-section can be seen in the success to describe the anisotropy of angular distribution of elastically backscattered electrons from Au in low energy region, shown in Fig.l. Fig.l(a) shows the elastic cross-sections of 600 eV electron for single Au-atom, clearly indicating that the angular distribution is no more smooth as expected from Rutherford scattering formula, but has the socalled lobes appearing at the large scattering angle.


Author(s):  
C J R Sheppard

The confocal microscope is now widely used in both biomedical and industrial applications for imaging, in three dimensions, objects with appreciable depth. There are now a range of different microscopes on the market, which have adopted a variety of different designs. The aim of this paper is to explore the effects on imaging performance of design parameters including the method of scanning, the type of detector, and the size and shape of the confocal aperture.It is becoming apparent that there is no such thing as an ideal confocal microscope: all systems have limitations and the best compromise depends on what the microscope is used for and how it is used. The most important compromise at present is between image quality and speed of scanning, which is particularly apparent when imaging with very weak signals. If great speed is not of importance, then the fundamental limitation for fluorescence imaging is the detection of sufficient numbers of photons before the fluorochrome bleaches.


2020 ◽  
Vol 23 (1) ◽  
pp. 66-71
Author(s):  
E. A. Gurnevich ◽  
I. V. Moroz

The Smith-Purcell radiation of a charged particle moving in a periodic structure is analysed theoretically. The considered structure consists of two planar diffraction gratings with different periods which are formed by parallel conducting wires. The analytical expression for the spectral-angular distribution of radiation is obtained. It is shown that the angular distribution of radiation can be made narrower by using two gratings instead of one, and radiation intensity can be manipulated by parallel relative shift of gratings. The obtained results are of great importance for the research and development of high power radiation sources based on volume free-electron lasers.


Currently, the professional construction community information field is largely filled with the topic of creating a comfortable living environment. However, architectural and engineering design that corresponds to the concept of sustainable development is currently hindered due to the lack of a formed conceptual framework that reveals the meaning of the term "comfort", as well as a criteria list that determines the indoor environment quality in the Russian Federation regulatory and technical framework. The article offers some components of a comfortable living environment, within which the parameters of designing the internal environment of premises are highlighted. A comparative analysis of the national standards of the Russian Federation regulating the design of the internal space of residential and public buildings, with international "green" standards for a number of parameters was carried out. It is concluded that it is necessary to update the Russian regulatory and technical base taking into account the international experience of "green" standards.


2016 ◽  
Vol 22 (2(99)) ◽  
pp. 48-51
Author(s):  
D.S. Kalynychenko ◽  
◽  
Ye.Yu. Baranov ◽  
M.V. Poluian ◽  
◽  
...  

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