Introduction: In recent decades, several Monte Carlo codes have been introduced for research and medical applications. These methods provide both accurate and detailed calculation of particle transport from linear accelerators. The main drawback of Monte Carlo techniques is the extremely long computing time that is required in order to obtain a dose distribution with good statistical accuracy. ...

We report the testing of a high gradient electron accelerator with a photonic-band-gap (PBG) structure. The photonic-band-gap structure confines a fundamental TM(01)-like accelerating mode, but does not support higher-order modes (HOM). The absence of HOM is a major advantage of the PBG accelerator, since it suppresses dangerous beam instabilities caused by wakefields. The PBG structure was des...

Traditionally, lead has been used for field shaping in megavoltage electron beams in radiation therapy. In this study, we analyze the dosimetric parameters of a nontoxic, high atomic number (Z = 83), bismuth-loaded material called Gamma Putty that is malleable and can be easily molded to any desired shape. First, we placed an ionization chamber at different depths in a solid water phantom under...

INTRODUCTION In radiotherapy, megaelectron volt (MeV) electrons are employed for treatment of superficial cancers. Magnetic fields can be used for deflection and deformation of the electron flow. A magnetic field is composed of non-uniform permanent magnets. The primary electrons are not mono-energetic and completely parallel. Calculation of electron beam deflection requires using complex mathe...

An electron beam microbunched on the optical wavelength scale of ø2.5 mm by an inverse free electron laser accelerator was observed. The optimum bunching was achieved for a 1% energy modulation of a 32 MeV electron beam with 0.5 GW CO2 laser power. The microbunching process was investigated by measuring the coherent transition radiation produced by the energy modulated electron beam. A quadrati...

In the interaction of a 30 fs, 40 TW Ti:sapphire Hercules laser focused to the intensity of 1019 W/cm2onto a supersonic He gas jet, we observed quasi-monoenergetic electron beams with energy up to 300 MeV and an angular divergence of 10 mrad. We found that the initial plasma density significantly affects the resultant electron beam. For plasma densities ranging between 2×1019 to 3.5×1019 cm−3, ...

The purpose of this work was to experimentally investigate the out-of-field dose in a water phantom, with several high energy electron beams used in external beam radiotherapy (RT). The study was carried out for 6, 9, 12, and 18 MeV electron beams, on three different linear accelerators, each equipped with a specific applicator. Measurements were performed in a water phantom, at different depth...

PURPOSE In this paper, the effect on image quality of significantly reducing the primary electron energy of a radiotherapy accelerator is investigated using a novel waveguide test piece. The waveguide contains a novel variable coupling device (rotovane), allowing for a wide continuously variable energy range of between 1.4 and 9 MeV suitable for both imaging and therapy. METHOD Imaging at lin...

The plasma wake-field mechanism can be used to couple energy at a high rate from a bunched electron beam into a plasma wave. We will present results from the Fermilab A0 facility where a beam with an initial energy of 14 MeV passes through the plasma to emerge with a much broader energy spread, spanning from a low of 3 MeV to a high of over 20 MeV. Over the 8 cm lenth of the 1014 cm 3 plasma, t...

From last 50 years, electron beam therapy has an important radiation therapy modality. The electron beam from the LINAC is of size ∼ 2 mm, whereas the size required for actual treatment is usually larger than 2 × 2 cm up to 25 × 25 cm at the isocenter. In the present work, it is proposed to use dual scattering foil system for production of clinical electron beam. The foils for 6 to 20 MeV elect...