Top-up Mode

Top-up is a mode of operation that aims to maintain a steady current in the storage ring by periodically injecting small amounts of current. It produces a more stable beam by keeping the heat loads and signal strengths constant over long time periods in both the storage ring and on the beamlines. Most of the third-generation light sources, including the Australian Synchrotron, are designed to run in top-up mode. Presently the APS, SLS, SSRL, ALS, SSRF, SOLEIL, Diamond, Spring8 and TLS operate in top-up mode. ESRF, BESSY, ALBA, and NSLS-II plan to move to top-up operation in the future. While the accelerator equipment was designed to accommodate top-up operation and it has been demonstrated in principle during machine studies shifts, there are many developments that will be necessary before top-up can be run reliably during user beam time. One of the first things that will need to be done is to study the injection process with a view to ensure that the injection into the storage ring with photon shutters opened to the beamlines can be done safely. Other developments may include, but are not limited to expanded diagnostic capabilities, primarily in the booster to storage ring transfer line, an energy limiting aperture in the transfer line, and increased local shielding. The fact that the injection system runs constantly makes it worthwhile to try to reduce the energy of the injection into the booster to the point where the linac can be run on a single klystron by modifying the existing RF distribution system possibly including SLED cavities. This would also free up a klystron that could be used for other development projects as described below.

pdf document Download Top-Up Mode Injection Project Proposal Here (pdf, 22kb)

 

Contact Greg LeBlanc
Position: Head of Accelerator Science and Operations, Australian Synchrotron
Phone: +61 (0)3 8540 4209
Fax: +61 (0)3 8540 4200
Email: [email protected]

Further Information