The Compton positron source of a future linear collider must obtain the target bunch population by accumulating a large number of positron packets, arriving either in a number of bursts from a ‘Compton ring’, with intermediate damping of the scattering electron beam, or quasicontinually from a ‘Compton energy recovery linac’. We present simulation results for the longitudinal stacking of Compto...

SLAC’s Advanced Computations Department (ACD) has developed the first parallel Finite Element 3D Particle-In-Cell (PIC) code, Pic3P, for simulations of RF guns and other spacecharge dominated beam-cavity interactions. Pic3P solves the complete set of Maxwell-Lorentz equations and thus includes space charge, retardation and wakefield effects from first principles. Pic3P uses higher-order Finite ...

The Linac Coherent Light Source is being constructed at the Stanford Linear Acceleration with a projected start of operations in 2008. A number of studies have been initiated for the for the purposes of determining the engineering specifications and tolerances for the fully built machine. This paper takes up a small part of the larger issue; examining the necessary tolerances for magnetic field...

Space charge can lead to emittance and/or energy exchange in non-equipartitioned high intensity linacs, which is interpreted here in terms of ”coherent resonance”. In this paper we first compare 2D and 3D simulations in constant focusing, and relate them to self-consistent resonant charts based on analytical theory. We then use these charts to interpret PARMILA simulation results for the SNS li...

In the 1994/95 SLC run, bunch lengthening in the damping ring along with overcompression in the two ring-to-linac transport lines (RTLs) have caused a normal beam loss of about 10-20% between entrance and end of the RTLs, which constitutes a major hindrance to further luminosity increases of the SLC. This paper summarizes studies of both longitudinal and six-dimensional dynamics in the RTL, and...

Spatially fractionated radiotherapy (GRID) was designed to treat large tumors while sparing skin, and it is usually delivered with a linear accelerator using a commercially available block or multileaf collimator (LINAC-GRID). For deep-seated (skin to tumor distance (> 8 cm)) tumors, it is always a challenge to achieve adequate tumor dose coverage. A novel method to perform GRID treatment using...

The European Spallation Source will be a 5 MW superconducting proton linac for the production of spallation neutrons. It is composed of an ion source, a radio frequency quadrupole, a drift tube linac and a superconducting linac as well as the low, medium and high, energy beam transport sections. At present these components of the linac are in the design phase: the optimization of the accelerato...

A water-cooled conical target for producing neutrons via the Li(p,n)Be reaction at 2.5 MeV is under development at Linac Systems. The target is intended to accept an expanded 50-kW beam from an rf linac, and is predicted to meet the intensity requirements for practical accelerator-based boron neutron capture therapy (BNCT) in concert with Linac Systems’ CW RFI linac[1]. Lithium metal targets pr...

One of the major challenges facing the proposed highenergy linear ee colliders is the preservation of the extremely small vertical emittance from the damping rings to the interaction point (IP). This emittance must be transported through bunch compression sections, the main linac and finally through the beam delivery system to the IP. Historically, the beam dynamics issues of each subsystem hav...