Author: Sessler, A.
Paper Title Page
TUPPP073 Machine Parameter Studies for an FEL Facility Using STAFF 1768
  • M.W. Reinsch, B. Austin, J.N. Corlett, L.R. Doolittle, P. Emma, G. Penn, D. Prosnitz, J. Qiang, A. Sessler, M. Venturini
    LBNL, Berkeley, California, USA
  • J.S. Wurtele
    UCB, Berkeley, California, USA
  Designing an FEL facility requires balancing multiple science needs, FEL and accelerator physics constraints, and engineering limitations. STAFF (System Trade Analysis for an FEL Facility) is a MATLAB program that enables the user to rapidly explore a large range of Linac and FEL design options to meet science requirements. The code uses analytical models such as the Ming Xie formulas when appropriate and look-up tables when necessary to maintain speed and flexibility. STAFF's modular design simplifies the inclusion of new physics models for FEL harmonics, wake fields, cavity higher-order modes and aspects of linac design such as the optimization of a laser heater, harmonic linearizer, and one or more bunch compressors. Code for the microbunching instability has been included as well. STAFF also supports multiple undulator technologies. STAFF permits the user to study error tolerances and multiple beamlines so as to explore the full capabilities of an entire user facility. This makes it possible to optimize the integrated system in terms of performance metrics such as photons/pulse, photons/sec and tunability range.  
THPPR054 Progress in the Design of a Curved Superconducting Dipole for a Therapy Gantry 4097
  • S. Caspi, D. Arbelaez, L.N. Brouwer, D.R. Dietderich, R.R. Hafalia, D. Robin, A. Sessler, C. Sun, W. Wan
    LBNL, Berkeley, California, USA
  A curved superconducting magnet for a carbon therapy gantry requires a large bore and a field around 5T. The design reduces the gantry’s size and weight and makes it more comparable with gantries used for proton therapy. In this paper we report on a combined function superconducting dipole magnet that is half the size needed for carbon gantry and is about the size of a proton gantry. The half scale, with a 130 mm bore diameter that is curved 90 degrees at a radius of 634 mm, superimposes two layers of oppositely wound and skewed solenoids that are energized in a way that nulls the solenoid field and doubles the dipole field. Furthermore, the combined architecture of the windings can create a selection of field terms that are off the near-pure dipole field. In this paper we report on the design of a two layers curved coil and the production of the winding mandrel. Some details on the magnet assembly are included.  
THPPR055 Compact Gantry with Large Momentum Acceptance 4100
  • W. Wan, D. Robin, A. Sessler, C. Sun
    LBNL, Berkeley, California, USA
  Rotatable Ion Beam Cancer Therapy (IBCT) delivery systems or gantries are the largest features in an ion beam therapy facility. They weight 100+ tons and require large (~3 story) heavily shielded rooms to house them. Reducing the size of ion beam gantries using high field One disadvantage of superconducting magnets is the difficulty of changing the fields quickly in order to adjust the beam momentum to scan the depth of penetration. In this paper we present a design of a gantry consisting of many combined function superconducting magnets that have a large enough momentum acceptance (> pm 10%) such that the magnets do not need to be changed while changing the beam energy.