Emittance and lifetime measurement with damping wigglers

Area of Science:

• Synchrotron Radiation
• Particle Accelerator Physics
• Materials Science

Background:

• The National Synchrotron Light Source II (NSLS-II) is a state-of-the-art storage ring light source.
• Achieving ultra-low emittance is crucial for high-resolution experimental capabilities.
• The NSLS-II lattice design incorporates double bend achromatic cells to achieve low horizontal emittance.

Purpose of the Study:

• To characterize the impact of Damping Wigglers (DWs) on NSLS-II storage ring performance.
• To evaluate the reduction in beam emittance achieved by DWs.
• To assess the effects of DWs on energy spread and beam lifetime.

Main Methods:

• Implementation of 30-cell double bend achromatic cells.
• Installation and utilization of multiple Damping Wigglers (DWs).
• Measurement of beam parameters using X-ray pinhole camera, beam position monitors, beam filling pattern monitor, and current transformers.

Main Results:

• DWs effectively reduce the horizontal emittance of the NSLS-II storage ring.
• Measured beam performance parameters are compared with analytic estimates for the DWs.
• Characterization of changes in energy spread and beam lifetime due to DW installation.

Conclusions:

• Damping Wigglers are a key component in achieving the NSLS-II's low emittance design goals.
• The experimental results validate the effectiveness of DWs in enhancing storage ring performance.
• The findings support the NSLS-II's capability for novel user experiments demanding high spatial and energy resolution.