The axial dose profile of various scans of different CTs was determined to obtain specification on radiation geometry by collimation. The dose was measured "free-in-air" by thermoluminescent dosimeters at the axis of rotation. Considerable differences between the various CTs were observed. The scans of different CTs had narrow and wide fields. It seems to be possible to reduce the energy transm...

We demonstrate that surface waves in structured perfect electric conductor surfaces can be self-collimated using the finite-difference time-domain method. The self-collimation frequency is obtained from the equi-frequency contours of a perfect electric conductor patterned with an array of square holes. The field patterns of the self-collimated surface wave, obtained using the periodic boundary ...

We describe linac protection and a conventional collimation system appqxiate for a next linear collider. The linac accelerating structure can be protected from “worst credible failures” by a system of sacrificial spoilers. For the collimation system we consider the effects of asverse wakefields and the transmission, heating, mechanical stress, and edge-scattering properties of scrapers. We requ...

The first results of an experimental campaign are reported in which it is intended to demonstrate whether it is possible for the fast electron beam (produced at irradiances in excess of 1019 Wcm−2μm2) to be artificially collimated even when the beam enters the target with a large divergence angle. The artificial collimation occurs because of a pre-generated magnetic field that is produced by a ...

We analyze, in three dimensions, the dispersion properties of dielectric slabs perforated with two-dimensional photonic crystals (PCs) of square symmetry. The band diagrams are calculated for all -vectors in the first Brillouin zone, and not only along the characteristic high-symmetry directions. We have analyzed the equal-frequency contours of the first two bands, and we found that the square ...

There are many types of display systems used in Augmented Reality (AR), each having specific application areas. Based on an extensive literature and technology review, this paper proposes the use of a transparent projection screen for users in a fixed position observing distant objects. The transparent projection screen is similar to head-up displays (HUDs) used in aircraft cockpits, since they...

The post-linac energy collimation system of CLIC is designed to fulfil an essential function of protection of the Beam Delivery System (BDS) against miss-steered beams generated by failure modes in the main linac. Guaranteeing the collimator survivability in case of direct beam impact is very challenging, if we take into account the need to deal with an unprecedented transverse energy density p...