SLAC, Menlo Park, California, USA
The SPEAR3 light source at SSRL was commissioned in 2004. Since that time the machine has undergone a continual program of improvements that has led to a lowering of the ring emittance, improved injection efficiencies, and the development of specialized operational modes. The effective use of beam diagnostics enabled these improvements to be tested and verified prior to their implementation. To optimize injection we needed to measure the beam position, size, shape, and arrival time of our injected bunch as well as beam losses in the ring. To test new lattices we used these diagnostics to characterize the non-linear resonances in the ring and therefore find operating points that maximized beam stability and lifetime. In this paper we discuss the electrical and optical instruments as well as the experimental methods we used to make these measurements.
UMD, College Park, Maryland, USA
SLAC, Menlo Park, California, USA
JLAB, Newport News, Virginia, USA
KEK, Ibaraki, Japan
We have applied a new imaging/optical masking technique, which employs a digital micro-mirror device (DMD) and optical synchrotron radiation (OSR), to perform high dynamic range (DR) beam imaging at the JLAB Energy Recovery Linac and the SLAC/SPEAR3 Synchrotron Light Source. The OSR from the beam is first focused onto the DMD to produce a primary image; selected areas of this image are spatially filtered by controlling the state of individual micro-mirrors; and finally, the filtered image is refocused onto a CCD camera. At JLAB this technique has been used successfully to view the beam halo with a DR ~ 105. At SPEAR3 the DMD was used to filter out the bright core of the stored beam to study the turn-by-turn dynamics of the 10-3 weaker injected beam. We describe the optical performance, present limitations and our plans to improve the DR of both experimental systems.