Understanding and Compensating Emittance Diluting Effects in Highly Optimized Ultrafast Electron Diffraction Beamlines
Pierce, C., Baturin, S., Bazarov, I., Gordon, M., Gulliford, C., Kim, Y.-K., & Maxson, J.
Brightness preservation in transport from low emittance photocathodes is an important challenge for the development of single-shot ultrafast electron diffraction. We show that the contributions of the space charge force on to the emittance can be separated from the effects of guide field aberrations via a new set of metrics. Additionally, core emittance was shown to be a better invariant than emittance itself. The limit to electron beam quality in single-shot time-resolved electron diffraction experiments was shown to be the electrons becoming disordered from their electrostatic repulsion. This result advances objective A in Beam Storage and Transport: "Identify and quantify 6D emittance dilution mechanisms from x100 brighter sources..." This paper benefits the application of single-shot ultrafast electron diffraction.