Skip to main content
eScholarship
Open Access Publications from the University of California

Scholarly Works (9 results)

  • Article
  • Peer Reviewed
LBL Publications (2008)
Elliptically Polarizing Undulators [1] that provide full photon polarization control also have fast, intrinsic transverse roll-off of the magnetic field. The roll-off is especially fast for vertical polarization settings, and can have big detrimental effects on the nonlinear single particle dynamics. Particularly low and medium energy light sources and long period EPUs are prone to those effects. The three existing 50 mm period EPUs at the ALS have been retrofitted with shims to correct for these dynamic multipole effects and a new 90 mm period device which otherwise would have caused a huge reduction in dynamic aperture has been shimmed before installation. Beam dynamics measurements on all devices show that the shimming works very well and user operation with the long period EPU has begun.
    Cover page: Shimming correction of dynamic multipole effects on APPLE-II type epus at the ALS
    • Article
    • Peer Reviewed
    LBL Publications (2010)
    The Advanced Light Source is one of the earliest 3rd generation light sources. With an active upgrade program it has remained competitive over the years. The latest in a series of upgrades is a lattice upgrade project that was started in 2009. When it will be completed, the ALS will operate with a horizontal emittance of 2.2 nm and an effective emittance of 2.6 nm. Combined with the high current of 500 mA and the small vertical emittance the ALS already operates at, this upgrade will keep it competitive for years to come. This paper summarizes the status of the upgrade, including beam dynamics studies and lattice optimizations as well as the magnet design.
      Cover page: Status of the low emittance upgrade of the advanced light source
      • Article
      • Peer Reviewed
      LBL Publications (2012)
      The Advanced Light Source (ALS) at Berkeley Lab while one of the earliest 3rdgeneration light sources remains one of the brightest sources for soft x-rays worldwide. Amultiyear upgrade of the ALS is currently under way, which includes new and replacementx-ray beamlines, a replacement of many of the original insertion devices and many upgradesto the accelerator. The accelerator upgrade that affects the ALS performance most directlyis the ALS brightness upgrade, which will reduce the horizontal emittance from 6.3 to 2.2nm (2.6 nm effective). This will result in a brightness increase by a factor of three forbendmagnet beamlines and at least a factor of two for insertion device beamlines. Magnetsfor this upgrade are currently in production and will be installed starting later thisyear. Copyright © 2012 by IEEE.
        Cover page: Status of the ALS brightness upgrade
        • Article
        • Peer Reviewed
        ALS-U (2014)
        The Advanced Light Source (ALS) at Berkeley Lab remains one of the brightest sources for soft x-rays worldwide. A multiyear upgrade of the ALS is underway, which 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 [1], which reduces the horizontal emittance from 6.3 to 2.0 nm (2.5 nm effective). Magnets for this upgrade were installed in late 2012 and early 2013 followed by user operation with the reduced emittance.
          Cover page: Completion of the Brightness Upgrade of the ALS
          • Article
          LBL Publications (2002)

          We present the concepts for a storage ring dedicated to and optimized for the production of stable coherent synchrotron radiation (CSR) over the far-infrar ed wavelength range from about 200 microns to 1 mm.

            Cover page: A dedicated storage ring for Far-IR coherent synchrotron radiation at the ALS
            • Article
            • Peer Reviewed
            LBL Publications (2013)
            The Advanced Light Source (ALS) at Berkeley Lab remains one of the brightest sources for soft x-rays worldwide. A multiyear upgrade of the ALS is underway, which 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 reduced the horizontal emittance from 6.3 to 2.0 nm (2.5 nm effective). Magnets for this upgrade were installed starting in 2012 followed by a transition to user operations with 2.0 nm emittance in spring 2013. Copyright © 2013 by JACoW.
              Cover page: Completion of the brightness upgrade of the ALS
              • Article
              • Peer Reviewed
              LBL Publications (2014)
              The Advanced Light Source (ALS) is a thirdgeneration light source in operation since 1993. This light source is providing state-of-the-art performance to more than 40 beamlines and their users, due to the upgrades that have been completed over the last few years. The storage ring upgrade project that is developed here will allow the ALS to provide the 40 beamline users with higher photon beam brightness (factor of 2 or 3) by having its storage ring lattice modified. Forty-eight harmonic sextupole magnets with integrated dipole correctors and skew quadrupole coils will be introduced, which will require a level of installation activity not seen at the ALS since its original construction in 1991. Introducing new combined-function magnets in an existing storage ring is a challenge due to the limited space available and a balance had to be found between magnet performance and spatial constraints. After an introduction reviewing the characteristics of the three design families of the 48 combined-function magnets, the magnet fabrication and installation are developed along with analyses based on the magnetic measurements and the ALS storage ring commissioning results.
                • Article
                • Peer Reviewed
                LBL Publications (2007)
                The Advanced Light Source is currently being upgraded for top-off operation. This major facility upgrade will provide an improvement in brightness from soft x-ray undulators of about one order of magnitude and keep the ALS competitive with the newest intermediate energy light sources. Major components of the upgrade include making the booster synchrotron capable of full energy operation, radiation safety studies, improvements to interlocks and collimation systems, diagnostics upgrades as well as emittance improvements in the main storage ring. Most hardware necessary as part of the upgrade has been installed and commissioned. The radiation safety studies are making good progress and have passed a first outside peer review succesfully. ©2007 IEEE.
                  • Article
                  Lawrence Berkeley National Laboratory (2004)

                  The Advanced Light Source (ALS) is a third generation synchrotron light source located at Lawrence Berkeley National Laboratory (LBNL). There was an increasing demand at the ALS for additional high brightness hard x-ray beamlines in the 7 to 40 keV range. Inresponse to that demand, the ALS storage ring was modified inAugust 2001. Three 1.3 Tesla normal conducting bending magnets were removed and replaced with three 5 Tesla superconducting magnets (Superbends). The radiation produced by these Superbends is an order of magnitude higher in photon brightness and flux at 12 keV than that of the 1.3 Tesla bends, making them excellent sources of hard x-rays for protein crystallography and other hard x-ray applications. At the same time the Superbends did not compromise the performance of the facility in the VUV and softx-ray regions of the spectrum. The Superbends will eventually feed 12 new beam lines greatly enhancing the facility's capability and capacity in the hard x-ray region. The Superbend project is the biggest upgrade to the ALS storage ring since it was commissioned in 1993. In this paper we present an overview of the Superbend project, its challenges and the resulting impact on the ALS.

                    Cover page: Superbend upgrade of the Advanced Light Source
                    Top