Large Rectangular Vacuum Windows

Stress Rupture Considerations in the Design of Large Aperture, Low Mass Composite Vacuum Windows

Large vacuum vessels are often employed in High Energy and Nuclear Physics experiments to provide a volume for particle traverse in the absence of air molecules. The ends of these vessels generally have a large aperture which is closed with a thin membrane known as a vacuum window. To minimize the vacuum window mass, composites of Kevlar and Mylar have been used in window construction. Historic...

Recursive Algorithms for Image Local Statistics in Non-rectangular Windows

A general framework is presented for recursive computation of image local statistics in sliding window of almost arbitrary shape with “per-pixel” computational complexity substantially lower than the window size. As special cases, recursive algorithms are described for computing image local statistics such as local mean, local variance, local kurtosis, local order statistics (minimum, maximum, ...

Vacuum polarization by a magnetic flux of special rectangular form

We consider the ground state energy of a spinor field in the background of a square well shaped magnetic flux tube. We use the zeta-function regu-larization and express the ground state energy as an integral involving the Jost function of a two dimensional scattering problem. We perform the renormalization by subtracting the contributions from first several heat kernel coefficients. The ground ...

Development and Measurement of Strain Free Rf Photoinjector Vacuum Windows *

RF photoinjectors produce the highest brightness electron bunches only under nearly ideal illumination by a drive laser [1]. The vacuum window used to introduce the laser beam is an essential element that may potentially degrade the distribution, making it difficult or impossible to know the actual uniformity achieved at the cathode. Because of the necessity to obtain ultrahigh vacuum near the ...

Leak Checking Large Vacuum Chambers