In recent work, a technique was developed to extract high quality beams from single-component plasmas confined in a Penning–Malmberg trap in a 4.8 T magnetic field. In this paper, a procedure is developed to extract these beams from the confining magnetic field and then focus them to create especially tailored electrostatic beams. Electron beams are extracted from the field in two stages: they ...

BACKGROUND AND PURPOSE A comprehensive dosimetry intercomparison has been carried out involving all the radiotherapy centres, all external beam modalities and every radiotherapy treatment unit in the Republic of Ireland. MATERIALS AND METHODS Reference point measurements were made for all megavoltage photon beams. Doses were also investigated in planned three-field distributions. One of these...

– We present a new dispersion relation for photons that are nonlinearly interacting with a radiation gas of arbitrary intensity due to photon–photon scattering. It is found that the photon phase velocity decreases with increasing radiation intensity, it and attains a minimum value in the limit of super-intense fields. By using Hamilton's ray equations, a self-consistent kinetic theory for inter...

Background: Multiple beams are generally used with an increased possibility that the beam axis intersects the treatment table. Treatment tabletops are commonly made of carbon fiber due to its high mechanical strength and rigidity, low specific density, extremely light and low radiation beam attenuation properties. Purpose of this paper is investigated the dose changes in the buildup region and ...

Control of microbunching instability is a fundamental requirement in modern high brightness electron linacs, in order to prevent malfunction of beam optical diagnostics and contamination in the generation of coherent radiation, such as free electron lasers. We present experimental control and suppression of microbunching instabilityinduced optical transition radiation by means of particles’ lon...

We consider the calculation of high energy hadron cascades induced by electron and photon beams in the GeV energy range. The most important source of high energy hadrons is the hadronic interaction of photons from the primary electron-photon shower. The hadronic interaction of high energy photons is described by the vector meson dominance model and by a Monte Carlo version of the dual multistri...

The three-dimensional evolution of a pure electron plasma is studied by means of a particle-in-cell code which solves the drift-Poisson system where kinetic effects in the motion parallel to the magnetic field are taken into account. Different results relevant to the nonlinear dynamics of trapped plasmas and low-energy electron beams are presented.

In order to utilize the electron beam of the Stanford two-mile accelerator most effectively, an elaborate beam switchyard will be used. Two basic components constitute the switchyard: a switching magnet 2nd two deflecting transport systems. A precision deflection magnet system containing several dc magnets and quadrupoles will bend and momentum-analyze the electron and positron beams. This pape...

This report is a self-contained and comprehensive review of the physics of propagating pulses of high-intensity high-energy particle beams in pre-existing or self-generated plasmas. Consideration is given to beams of electrons, protons, muons, and their antiparticles, as well as to neutral-hydrogen, positronium, and electron-positron-plasmoid beams. The first part is a systematic overview of th...