23–28 Aug 2026
America/Los_Angeles timezone

An alternative method to generate CW electron beams for Hard X-ray FEL

THA01
27 Aug 2026, 09:30
20m
Contributed Oral Presentation Session 7: Electron Sources Electron Sources (Contributed)

Speaker

Nikhil Bachhawat (Stony Brook University)

Description

The generation of high-quality continuous-wave (CW) electron beams with parameters suitable for hard X-ray free-electron lasers (FELs) has so far not been demonstrated experimentally. Traditionally, photoinjectors operating at very high accelerating gradients are considered necessary to meet the stringent beam-quality requirements of hard X-ray FELs. While high-gradient guns have been successfully operated in pulsed mode, extending this approach to CW operation is technically challenging, and can lead to excessive field emission (dark current) and reduced photocathode lifetime.

In this talk, I will present our results demonstrating that an alternative approach using a superconducting radiofrequency (SRF) gun with a modest accelerating gradient of approximately 15 MV/m, combined with a ballistic compression beamline, can produce CW electron beams with the required parameters. I will present a detailed description of the accelerator system and report measurements of projected (0.2 mm-mrad @ 100 pC) and slice transverse emittances (0.15 mm-mrad @ 100 pC), as well as the bunch’s longitudinal phase space. The experimental results will also be compared with start-to-end simulations.

Funding Agency

DE-SC0021426 award from the U.S. Department of Energy Office of Nuclear Physics and by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704

I have read and accept the Privacy Policy Statement Yes

Author

Nikhil Bachhawat (Stony Brook University)

Co-authors

Gang Wang (Brookhaven National Laboratory) Igor Pinayev (Brookhaven National Laboratory) Jean Clifford Brutus (Brookhaven National Laboratory) John Skaritka (Brookhaven National Laboratory) Jun Ma (Brookhaven National Laboratory) Luca Cultrera (Brookhaven National Laboratory) Patrick Inacker-Mix (Brookhaven National Laboratory) Vladimir Litvinenko (Stony Brook University) Yichao Jing (Brookhaven National Laboratory)

Presentation materials

There are no materials yet.