SPring-8 in-vacuum undulator beam test at the ESRF

Area of Science:

• Synchrotron Radiation Technology
• Particle Accelerator Physics

Background:

• The development of advanced insertion devices like in-vacuum undulators is crucial for enhancing synchrotron radiation sources.
• SPring-8's in-vacuum hybrid undulator was tested at the European Synchrotron Radiation Facility (ESRF) prior to SPring-8's commissioning.

Purpose of the Study:

• To evaluate the performance of the SPring-8 in-vacuum undulator during its initial beam test.
• To assess the impact of the undulator on the electron beam characteristics.
• To verify the integrity and functionality of the undulator's vacuum system.

Main Methods:

• The in-vacuum hybrid undulator was installed and operated at the ESRF.
• Beam diagnostics were employed to monitor the electron beam properties.
• The vacuum system performance within the undulator was closely monitored.

Main Results:

• The beam test provided initial insights into the undulator's interaction with the electron beam.
• A critical issue identified was the significant heating of the undulator components.
• This heating was attributed to the resistive wall impedance of the undulator.

Conclusions:

• Resistive wall impedance presents a substantial challenge for the operation of in-vacuum undulators.
• Further research and engineering solutions are necessary to mitigate heating effects for reliable undulator performance.