The Relativistic Heavy Ion Collider (RHIC) will experience increasing longitudinal and transverse heavy ion emittances, mostly due to intra-beam scattering (IBS). The experiments in RHIC are expected to not only have reduced luminosi-ties due to IBS but also an unwanted beam halo. Primary betatron collimators will be used to remove the large amplitude particles. The efficiency of the primary co...

A plasma spectrometer design based on advances in lithography and microchip stacking technologies is described. A series of curved plate energy analyzers, with an integrated collimator, is etched into a silicon wafer. Tests of spectrometer elements, the energy analyzer and collimator, were performed with a 5 keV electron beam. The measured collimator transmission and energy selectivity were in ...

ID: 10351 Title: Advances in arc therapy Intensity Modulated Arc Therapy: Technology and Clinical Implementation Cedric X. Yu University of Maryland School of Medicine AbstractID: 10351 Title: Advances in arc therapyID: 10351 Title: Advances in arc therapy Abstract Intensity modulated arc therapy (IMAT) was proposed by Yu as an alternative to Tomotherapy. Over more than a decade, many progresse...

We analyzed the physical basics for design of absorbers for high energy beams of electrons and photons. Typical examples are the collimators and dump systems. In particular, we considered a collimator for usage in Cornell ERL project, where it could be used for reduction of γ , − e halo, minimization of exposure SRF module to SR from neighboring bending magnet and for absorption of direct beam ...

For a short bunch in an elliptical collimator we demonstrate that, as in a purely round collimator, the wake can be estimated from the primary fields of the beam alone. We obtain the wakes in the LCLS rectangular-to-round, undulator transitions using a hybrid method that includes indirect numerical (field) integration and an analytical potential energy term. For the LCLS 1 nC bunch charge confi...

A comparison of image quality and dose delivered between two differing computed tomography (CT) imaging modalities-fan beam and cone beam-was performed. A literature review of quantitative analyses for various image quality aspects such as uniformity, signal-to-noise ratio, artifact presence, spatial resolution, modulation transfer function (MTF), and low contrast resolution was generated. With...

background: radiosurgery is a focal brain irradiation technique that delivers, usually in a single session, high dose of ionizing radiation. the presence of lateral electronic disequilibrium and steep dose gradients in small fields demands special attention to the selection of a suitable detector with respect to its size, composition and response. materials and methods : small circular fields w...

Introduction The ZAP-X is a novel self-contained and first-of-its-kind self-shielded therapeutic radiation device dedicated to brain and head and neck radiosurgery. By utilizing a 2.7-MV linear accelerator and incorporating a design in which a beam stop and major mechanical elements serve a radiation shielding function, the Zap-X does not typically require a radiation bunker. The unique collima...

The problem of the reconstruction of binary matrices from their fan-beam projections is investigated here. A fan-beam projection model is implemented and afterwards employed in systematic experiments to determine the optimal parameter values for a data acquisition and reconstruction algorithm. The fan-beam model, the reconstruction algorithm which uses the optimization method of Simulated Annea...

We have calculated the dose enhancements close to metal implants in Gamma Knife radiosurgery using different beam sizes, i.e., 4, 8 and 18 mm collimator helmets sin addition to the previous calculations using the 14 mm collimator helmetd. For the 8 and 18 mm helmets, the obtained results were similar to those obtained using the 14 mm helmet, which can be explained by the similar beam profiles w...