Author: Steier, C.
Paper Title Page
TUOCS3 Status of the ALS Upgrade 769
 
  • C. Steier, B.J. Bailey, A. Biocca, A.T. Black, D. Colomb, N. Li, A. Madur, S. Marks, H. Nishimura, G.C. Pappas, G.J. Portmann, S. Prestemon, D. Robin, S.L. Rossi, F. Sannibale, T. Scarvie, D. Schlueter, C. Sun, W. Wan
    LBNL, Berkeley, California, USA
 
  Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231
The Advanced Light Source (ALS) at Berkeley Lab is one of the earliest 3rd generation light sources. Over the years substantial upgrades have been implemented to keep the facility at the forefront of soft x-ray sources. The most recent one is a multi-year upgrade, that includes new and replacement x-ray beamlines, a replacement of many of the original insertion devices and many upgrades to the accelerator. The accelerator upgrade that affects the ALS performance most directly is the ALS brightness upgrade, which will reduce the horizontal emittance from 6.3 to 2.2 nm. This will result in a brightness increase by a factor of three for bend magnet beamlines and at least a factor of two for insertion device beamlines and will keep the ALS competitive with newer sources.
 
slides icon Slides TUOCS3 [4.970 MB]  
 
TUODN4 Dynamic Aperture Optimization using Genetic Algorithms 793
 
  • C. Sun, H. Nishimura, D. Robin, C. Steier, W. Wan
    LBNL, Berkeley, California, USA
 
  Genetic Algorithm is successfully applied to optimize dynamic aperture of lattices for ALS future upgrades. It is demonstrated that the optimization using total diffusion rate as objective has a better performance than the one using dynamic aperture area. The linear and non-linear properties of the lattice are optimized simultaneously, and trade-offs are found among the small emittance, low-beta function and large dynamic aperture. These trade-offs can provide us a guideline to choose a candidate lattice for ALS future upgrades.  
slides icon Slides TUODN4 [1.781 MB]  
 
TUP195 Commissioning the ALS Digital Power Supply Controller in the Booster Dipole and Quadrupole Magnet Power Supplies 1190
 
  • J.M. Weber, T. Scarvie, C. Steier, CA. Timossi
    LBNL, Berkeley, California, USA
 
  Funding: Supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The Advanced Light Source (ALS) is a third generation synchrotron light source that has been operating since 1993 at Berkeley Lab. A few years ago, the ALS was upgraded to achieve Top-Off Mode, which required replacing the booster dipole and quadrupole magnet power supplies to increase the peak booster beam energy from 1.5GeV to 1.9GeV. The original analog controller for each power supply has been replaced by a digital power supply controller (DPSC) to improve stability and resolution and provide a remote interface. The DPSC capabilities include 24-bit 100k-point digital reference waveform download and voltage reference generation, and complete digital current loop implementation. The hardware includes an FPGA with an embedded processor running a full EPICS IOC on VxWorks. This paper will present the current functionality of the DPSC as well as performance results from recent commissioning.

 
 
WEP031 Low-Emittance Lattice Designs for ALS Ultimate Upgrade 1549
 
  • C. Sun, H. Nishimura, D. Robin, C. Steier, W. Wan
    LBNL, Berkeley, California, USA
 
  Based upon the Theoretical Minimum Emittance (TME) technique, a new method has been developed to optimize low-emittance and low-beta lattices for further brightness upgrades at the Advanced Light Source (ALS). The study provides us a different perspective on the lattice design, and confirms results earlier found using both Global Scan of All Stable Settings (GLASS) and Genetic Algorithms (GA) techniques. Since the optimal low-beta lattice may have a dynamic aperture too small to allow off-axis injection, to overcome this problem, an alternating high-low beta lattice could be used for the upgrade. Several options of these high-low beta lattices are investigated using Genetic Algorithms.  
 
THP120 Light Sources Optimized with Super Bends 2342
 
  • L. Emery
    ANL, Argonne, USA
  • C. Steier
    LBNL, Berkeley, California, USA
 
  Funding: Work at Argonne was supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06CH11357
In the past small storage rings with dipole-magnet-only sources were called second-generation light sources (before insertion devices (IDs) were used). With today's technology, e.g. superconducting dipole magnet of 5 T (e.g., ALS's Superbend *), one could make a smaller ring (say, 60-m circumference) with substantial brightness for dipole-magnet beams. Without IDs, these optimized sources would be designated as between second and third generation. Such rings don't exist yet, but their concept can be compared with other types of compact light sources. Typical parameters of such ring would be 60-m circumference, 2 GeV, several 5-T dipole sources in TME-like cells, and 4x1013 photons/s/0.1% BW at 1 Angstrom. The number of beamlines is variable, but potentially very large, only limited by funding.
* D. Robin et al., NIM A 538, 1-3, (2005), 65-92.