Beam-based setup of the LHC collimators is necessary to establish the beam centers and beam sizes at the collimator locations and determine the operational settings during various stages of the LHC machine cycle. Automatic software algorithms have been successful in reducing the costly beam time required for the alignment, as well as significantly reducing human error. In this paper, the beam-b...

Katsevich’s inversion formula for helical tomography is explored in the limit of vanishing pitch, yielding a general reconstruction formula for fan-beam tomography. The relationship of this formula to other formulas in the literature is explored and a rigorous proof of a rebinning formula relating parallel-beam and fan-beam tomography is given. For the case of curved detector coordinates severa...

In this paper, we present a new algorithm designed for a specific data truncation problem in fan-beam CT. We consider a scanning configuration in which the fan-beam projection data are acquired from an asymmetrically positioned half-sized detector. Namely, the asymmetric detector only covers one half of the scanning field of view. Thus, the acquired fan-beam projection data are truncated at eve...

This paper discusses some notes on the vibration design for the piezoelectric cooling fan. After reviewing the fundamental formulas of the cantilever Euler beam, it is not easy to find the optimal design of the piezoelectric fan. The experiments also show the complicated results of the vibration behavior and air flow. Keywords—Piezoelectric cooling fan, vibration, cantilever Euler beam, air flow.

Highly efficient fan-out elements are crucial in coherent beam combining architectures especially in coupled laser resonators where the beam passes through the fan-out element twice per round trip. Although the theoretical efficiency is usually less than 86%, the Dammann gratings are ubiquitously utilized in a variety of types of coherent beam combining systems due to the facile design and fabr...

Electron Lenses built and installed in Tevatron have proven themselves as safe and very reliable instruments which can be effectively used in hadron collider operation for a number of applications, including compensation of beam-beam effects [1], DC beam removal from abort gaps [2], as a diagnostic tool. In this presentation we – following original proposal [3] – consider in more detail a possi...

In order to have highly flexible secondary beamlines collimation is crucial. Collimators are blocks of material placed along the beamline that let main beam pass within collimator aperture limits, while most particles beyond it interact in and gets absorbed or loses enough energy be deflected away from core by magnets downstream. Some can at edge collimators accepted beam, creating background f...

S.Y. Zhang Brookhaven National Laboratory, Upton, lWZ USA CWJ-j perpendicular rncident hasanangle8= O,and a range of Secondary electron (SE) production is briefly reviewed. If the collimator of the SNS storage ring allows proton beam scraping to take place, the electron yield might be quite large. At the AGS Booster, by steering the AU3’+ ion beam into the electrostatic rnflector,beam scraping ...

UNLABELLED The main objective of this work was the development of a skew-slit collimator for small-animal SPECT to replace the state-of-the-art multipinhole collimator. METHODS A pinhole forms a cone-beam imaging geometry. If the collimator rotates around the object in a circular orbit, the projection measurements acquired by the cone-beam imaging geometry are incomplete and not enough for ar...