Study of Radial Particle Flux due to Phase Difference Between Potential and Density Fluctuations

2009 ◽  
Vol 55 (2T) ◽  
pp. 168-171 ◽  
Author(s):  
Yoshiaki Miyata ◽  
Masayuki Yoshikawa ◽  
Masanori Mizuguchi ◽  
Youhei Oono ◽  
Yousuke Nakashima ◽  
...  
Keyword(s):  
Phase Difference ◽  
Particle Flux ◽  
Density Fluctuations

Measurement of axial phase difference of density fluctuations owing to spontaneously excited waves by using microwave reflectometer on GAMMA 10/PDX

2021 ◽  
Vol 92 (5) ◽  
pp. 053506
Author(s):  
R. Sekine ◽  
M. Hirata ◽  
R. Ikezoe ◽  
S. Jang ◽  
Y. Kubota ◽  
...  
Keyword(s):  
Phase Difference ◽  
Density Fluctuations

Radiation Damage, Contrast and Statistics in High Resolution Biological Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 260-261
Author(s):  
Robert M. Glaeser
Keyword(s):  
High Resolution ◽  
Particle Flux ◽  
Unit Area ◽  
Signal To Noise ◽  
Resolution Image ◽  
High Resolution Image ◽  
Pass Through ◽  
Counting Statistics ◽  
The Relationship ◽  
Picture Element

It is well known that a large flux of electrons must pass through a specimen in order to obtain a high resolution image while a smaller particle flux is satisfactory for a low resolution image. The minimum particle flux that is required depends upon the contrast in the image and the signal-to-noise (S/N) ratio at which the data are considered acceptable. For a given S/N associated with statistical fluxtuations, the relationship between contrast and “counting statistics” is s131_eqn1, where C = contrast; r2 is the area of a picture element corresponding to the resolution, r; N is the number of electrons incident per unit area of the specimen; f is the fraction of electrons that contribute to formation of the image, relative to the total number of electrons incident upon the object.

In situ irradiation effects studies in medium- and high-voltage TEM

1995 ◽  
Vol 53 ◽  
pp. 234-235
Author(s):  
Charles W. Allen
Keyword(s):  
Cross Section ◽  
Particle Flux ◽  
Threshold Value ◽  
High Energy ◽  
Irradiation Damage ◽  
Defect Complexes ◽  
Lattice Position ◽  
Electrons And Ions ◽  
The Masses

With respect to structural consequences within a material, energetic electrons, above a threshold value of energy characteristic of a particular material, produce vacancy-interstial pairs (Frenkel pairs) by displacement of individual atoms, as illustrated for several materials in Table 1. Ion projectiles produce cascades of Frenkel pairs. Such displacement cascades result from high energy primary knock-on atoms which produce many secondary defects. These defects rearrange to form a variety of defect complexes on the time scale of tens of picoseconds following the primary displacement. A convenient measure of the extent of irradiation damage, both for electrons and ions, is the number of displacements per atom (dpa). 1 dpa means, on average, each atom in the irradiated region of material has been displaced once from its original lattice position. Displacement rate (dpa/s) is proportional to particle flux (cm-2s-1), the proportionality factor being the “displacement cross-section” σD (cm2). The cross-section σD depends mainly on the masses of target and projectile and on the kinetic energy of the projectile particle.

What Is The Best Distance And Phase Difference Between The Elements Of Linear Antnna Array

2017 ◽  
pp. 1
Author(s):  
Asma M. N. El Ferjani ◽  
Ahmed S. El Barsha ◽  
AlZaroog Saleh Abdulali
Keyword(s):  
Phase Difference
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