Introduction: The head scatter factor (Sc) is important to measurements radiation beam and beam modeling of treatment planning systems used for advanced radiation therapy techniques. This study aimed to investigate the design of a mini-phantom to measurement variations in collimator Sc in the presence of shielding blocks for shaping the beam using different field sizes. <str...

The MInes NEutron Radiography (MINER) facility provides students and researchers at the Colorado School of Mines with the capability to perform neutron imaging at the Geological Survey TRIGA Reactor (GSTR). The current beamline consists of a 1.5 inch innerdiameter aluminum pipe routed from the reactor up to an experiment station in the reactor bay. There are several limitations associated with ...

Prolonged treatment execution time is a concern in CyberKnife robotic radiosurgery. Beam reduction and node reduction technique, and monitor unit optimization methods are adopted to reduce the treatment time. Usage of single collimator in the CyberKnife treatment plan can potentially reduce collimator exchange time. An optimal single collimator, which yields an acceptable dose distribution alon...

Background: One of the main problems of dedicated IORT accelerators is to determine dosimetric characteristics of the electron beams. Monte Carlo simulation of IORT accelerator head and produced beam will be useful to improve the accuracy of beam dosimetry.Materials and Methods: Liac accelerator head was modeled using the BEAMnrcMonte Carlo simulation system. Phase-space files were generated at...

Super-collimation is the propagation of a light beam without spreading that occurs when the light beam is guided by the dispersion properties of a photonic crystal, rather than by defects in the photonic crystal. Super-collimation has many potential applications, the most straight-forward of which is in the area of integrated optical circuits, where super-collimation can be utilized for optical...

Gradient-index dielectric lenses are generated based on the coordinate transformation by compressing the homogeneous air spaces quasi-conformally towards and outwards the primary source. The three-dimensional modeling is then performed through revolving the prescribed transformational media 180 degrees around the focal point to reach the architecture of barrel-vaults. It is found that all these...

Space Dynamics Laboratory at Utah State University (SDL/IJSU) optimized the focus of an off-axis, cryogenically cooled infrared collimator for cryogenic operating temperatures. Historically, collimator focus was optimized at ambient temperatures where interactive focus adjustment and testing coulà be performed. The focus shift that occurred when the optics were cooled was minimized by collimato...

The accuracy of single-beam dose profiles used in the algorithm of the Gamma Knife treatment planning system (Leksell GammaPlan) is verified. EGS4 Monte Carlo calculation was employed to calculate the dose distributions of single-beams in a spherical water phantom with diameter 160 mm. The beams were directed to the center of the phantom. Collimators of 4, 8, 14, and 18 mm sizes were studied. T...

The Leksell stereotactic Gamma Knifetrade mark uses radiation from 201 (60)Co sources that are focused to the center of a collimator helmet to deliver a high dose of radiation with minimal irradiation of proximal structures. This paper presents a method for fast verification of the irradiation time as calculated by the Leksell Gamma Knifetrade mark treatment planning software GammaPlan((R)). To...