Probing the barrier for CH2CHCO→CH2CH+CO by the velocity map imaging method

2005 ◽  
Vol 123 (5) ◽  
pp. 054322 ◽  
Author(s):  
K.-C. Lau ◽  
Y. Liu ◽  
L. J. Butler
Keyword(s):  
Velocity Map Imaging ◽  
Imaging Method

Three-dimensional (3D) velocity map imaging: from technique to application

2022 ◽  
Author(s):  
Gihan Basnayake ◽  
Yasashri Ranathunga ◽  
Suk Kyoung Lee ◽  
Wen Li
Keyword(s):  
Three Dimensional ◽  
Cost Effective ◽  
Velocity Map Imaging ◽  
Imaging Method ◽  
Translational Energy ◽  
Ion Imaging ◽  
Standard Tool ◽  
Recent Advancement ◽  
Acquisition Speed ◽  
Energy And Angular Distributions

Abstract The velocity map imaging (VMI) technique was first introduced by Eppink and Parker in 1997, as an improvement to the original ion imaging method by Houston and Chandler in 1987. The method has gained huge popularity over the past two decades and has become a standard tool for measuring high-resolution translational energy and angular distributions of ions and electrons. VMI has evolved gradually from 2D momentum measurements to 3D measurements with various implementations and configurations. The most recent advancement has brought unprecedented 3D performance to the technique in terms of resolutions (both spatial and temporal), multi-hit capability as well as acquisition speed while maintaining many attractive attributes afforded by conventional VMI such as being simple, cost-effective, visually appealing and versatile. In this tutorial we will discuss many technical aspects of the recent advancement and its application in probing correlated chemical dynamics.

Weak Beam Imaging and Diffraction Studies of Stacking Faults in Silicon

1976 ◽  
Vol 34 ◽  
pp. 590-591
Author(s):  
T. Y. Tan ◽  
W. K. Tice
Keyword(s):  
Fast Neutron ◽  
Rapid Determination ◽  
Stacking Faults ◽  
Imaging Method ◽  
Large Reduction ◽  
Dislocation Loops ◽  
Fringe Spacing ◽  
Weak Beam ◽  
Kinematical Theory

In studying ion implanted semiconductors and fast neutron irradiated metals, the need for characterizing small dislocation loops having diameters of a few hundred angstrom units usually arises. The weak beam imaging method is a powerful technique for analyzing these loops. Because of the large reduction in stacking fault (SF) fringe spacing at large sg, this method allows for a rapid determination of whether the loop is faulted, and, hence, whether it is a perfect or a Frank partial loop. This method was first used by Bicknell to image small faulted loops in boron implanted silicon. He explained the fringe spacing by kinematical theory, i.e., ≃l/(Sg) in the fault fringe in depth oscillation. The fault image contrast formation mechanism is, however, really more complicated.

Performance and applications of the holography electron microscope

1993 ◽  
Vol 51 ◽  
pp. 1078-1079
Author(s):  
Akira Tonomura
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Phase Measurement ◽  
Electron Holography ◽  
Imaging Method ◽  
High Contrast ◽  
Magnetic Lens ◽  
High Brightness ◽  
Holographic Imaging ◽  
Dynamic Observation

Electron holography is a two-step imaging method. However, the ultimate performance of holographic imaging is mainly determined by the brightness of the electron beam used in the hologram-formation process. In our 350kV holography electron microscope (see Fig. 1), the decrease in the inherently high brightness of field-emitted electrons is minimized by superposing a magnetic lens in the gun, for a resulting value of 2 × 109 A/cm2 sr. This high brightness has lead to the following distinguished features. The minimum spacing (d) of carrier fringes is d = 0.09 Å, thus allowing a reconstructed image with a resolution, at least in principle, as high as 3d=0.3 Å. The precision in phase measurement can be as high as 2π/100, since the position of fringes can be known precisely from a high-contrast hologram formed under highly collimated illumination. Dynamic observation becomes possible because the current density is high.

Fast low-radiation Flash-CT-scan - An alternative imaging method in patients with congenital heart disease?

2011 ◽  
Vol 59 (S 01) ◽  
Author(s):  
S Ihlenburg ◽  
A Rüffer ◽  
T Radkow ◽  
A Purbojo ◽  
M Glöckler ◽  
...  
Keyword(s):  
Congenital Heart Disease ◽  
Heart Disease ◽  
Ct Scan ◽  
Congenital Heart ◽  
Imaging Method
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