Progress towards top-up mode operations at the Advanced Photon Source

Conference · Tue Oct 26 04:00:00 EDT 1999

OSTI ID:750547

Emery, L; Borland, M

The Advanced Photon Source (APS) is a 7-GeV, third-generation synchrotron radiation source. To provide a more stable beam for users, in September 1998 the authors began commissioning a new operating mode called top-up. In this mode, the beam current does not decay but is maintained at a high level using frequent injection, while photon shutters are open and photon beams are delivered to users. The exhaustive analysis for top-up safety will be reviewed as well as the hardware and software required for top-up operation. Operational experience so far includes testing aspects of top-up injection, delivering beam to X-ray users for a few hours with fractional current stability of 0.001, and routinely providing beam to users by refilling the ring to 100 mA every 12 hours with shutters open. Top-up performance issues encountered are short-lived orbit and emittance transients during the injection event, which appear in user experiments as X-ray beam brightness dips. Planned system modifications to reduce these beam transients are described. The main operational issue left for continuous top-up injection will then be sharing the injector system with other operations.

• Research Organization: Argonne National Lab., IL (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 750547
• Report Number(s): ANL/AOD/CP-100239
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ADVANCED PHOTON SOURCE
BEAM CURRENTS
BEAM DYNAMICS
BEAM EMITTANCE
BEAM TRANSPORT
OPERATION
PERFORMANCE
SAFETY