1. INTRODUCTION X-ray sources on next generation low emittance/high brilliance synchrotrons such as the 7-GeV Advanced Photon Source (APS) (1) have unique properties which directly affect the design of the front end of the beam line. The most striking of these are the large peak photon power densities expected for the insertion device (ID) x-ray sources. Undulators. for example. can have highly...

Recent progress in high power laser development has attracted a growing interest in generating x-rays by Compton (or Thomson) backscattering an intense laser pulse off a high energy electron beam [1,2]. If λ L is the laser wavelength, γ is the electron energy in units of its rest mass mec , and θ is the angle of the scattered x-ray photon with respect to the direction of the electron trajectory...

Beam position monitor (BPM) characterization has been widely studied at the synchrotron. The characteristic impedance of a stripline BPM was designed using simulation and measured time-domain reflectometer method. mechanical electrical parameters feedthroughs with buttons used for BPMs were measured. Special care taken in analysis consistency four channels BPM. sorted based on their capacitance...

Introduction: In radiation therapy, the accuracy of dose calculations by a treatment planning system (TPS) is important to achieve tumor control and to spare normal tissue. Treatment planning system calculations in the heterogeneous situation may present significant inaccuracies. In this study, three different dose calculation algorithms, pencil beam (PB), collapsed cone (CC), ...

in high-energy photon interactions with a nucleus A, as recently suggested in [7] (slide 23). Of course, muon-pair production by this process is suppressed relative to electron-positron pair production by the ratio (me/mμ) 2 ≈ 1/40, 000, so there is an issue of the efficiency of muon production via reaction (1). The Bethe-Heitler process (1) is further suppressed near threshold, so it would be ...

The design of the 1-2 GeV Synchrotron Radiation Source to be built at the Lawrence Berkeley Laboratory is described. The goal of this facility is to provide very high brightness photon beams in the ultraviolet and soft X -ray regions. The photon energy nnge to be served is from 0.5 eV to 10 keY, with the brightest beams available in the I eV I keY interval. For time-resolved experiments, beam p...

It has been recognized that e+epair creation during the collision of intense beams in linear colliders will cause potential background problems for high energy experiments. Detailed knowledge of the angular-momentum spectrum of these low energy pairs is essential to the design of the interaction region. In this paper, we modify the computer code ABEL(Analysis of Beam-beam Effects in Linear coll...

Computational models of the human body have gradually become crucial in the evaluation of doses absorbed by organs. However, individuals may differ considerably in terms of organ size and shape. In this study, the authors sought to determine the energy-dependent standard deviations due to lung size of the dose absorbed by the lung during external photon and neutron beam exposures. One hundred l...

Background: Given the importance of scattered and low doses in secondary cancer caused by radiation treatment, the point dose of critical organs, which were not subjected to radiation treatment in breast cancer radiotherapy, was measured.Objective: The purpose of this study is to evaluate the peripheral dose in two techniques of breast cancer radiotherapy with two energies. Methods: Eight diff...

We discuss the experimental issues confronting measurements of the virtualCompton-scattering (VCS) reaction ep→epγ with electron beams of energy 6 – 30 GeV. We specifically address the kinematics of deeply-virtual-Comptonscattering (deep inelastic scattering, with coincident detection of the exclusive real photon nearly parallel to the virtual photon direction) and large transverse momentum VCS...