Yuan Shen Li’s PhD Thesis Defense

11:00 am–12:00 pm

Please Join us:

Yuan Shen Li's PhD Thesis Defense

Tuesday, April 25, 2023 at 11:00 am CDT

TRANSVERSE GRADIENT UNDULATOR IN A STORAGE RING FREE ELECTRON LASER OSCILLATOR

Accelerator-driven light sources, such as electron storage rings (SRs) and free-electron lasers (FELs), are valuable instruments of scientific discovery thanks to their unparalleled ability to produce extremely bright beams of X-ray light. In this talk, we will discuss the implementation of the storage ring X-ray FEL oscillator (SRXFELO). The SRXFELO has the potential to combine the strengths of the SR and FEL, thereby surpassing the performance of both in terms of average photon brightness and coherence. Our discussion will be based on a mix of theory and simulation.

We begin with an introduction to foundational concepts in SRs and FELs. This is followed by a discussion of the transverse gradient undulator (TGU) as a method to mitigate the SR energy spread deficiency. Next, we examine a custom simulation framework constructed as a start-to-end numerical model of the SRXFELO. We use this framework to simulate a hypothetical SRXFELO design based on realistic machine parameters, and report on projected performance and implementation strategies. Finally, we examine challenges associated with the X-ray cavity, such as beam alignment and optical phase purity, in the context of the Cavity-based X-ray FEL (CBXFEL) experiment located at SLAC.

Committee Members:
Kwang-Je Kim (Co-chair)
Young-Kee Kim (Co-chair)
Henry Frisch
Sergei Nagaitsev
Philippe Guyot-Sionnest

Yuan Shen will be starting as an Applications Engineer for COMSOL in Burlington, MA.

Event Type

Thesis Defense

Apr 25