19–24 May 2024
Music City Center
US/Central timezone

Dark current in the LCLS Injector: characterization and mitigation strategies

WEPC75
22 May 2024, 16:00
2h
Country (MCC Exhibit Hall A)

Country

MCC Exhibit Hall A

Poster Presentation MC2.T02 Electron Sources Wednesday Poster Session

Speaker

Sean Littleton (Stanford University)

Description

In addition to the desired electron beam, RF photoinjectors such as the one in LCLS-II produce dark current via field emission. Left unchecked, the dark current can cause various operational issues in the accelerator, such as increased radiation, damage to accelerator components and diagnostics, and desorption of gases from vacuum chamber surfaces. In this contribution, we present measurements of the dark current in the LCLS-II injector, including imaging, current, and energy distributions of the observed dark current emitters. These measurements allow us to characterize each emitter in terms of the Fowler-Nordheim model of field emission, which in turn enables us to more accurately model the behavior of the dark current in the accelerator. Taking these results into account, we also present potential active and passive mitigation strategies.

Funding Agency

U.S. DOE Contract No. DE-AC02-76SF00515

Region represented North America
Paper preparation format LaTeX

Primary author

Sean Littleton (Stanford University)

Co-authors

David Dowell (SLAC National Accelerator Laboratory) Feng Zhou (SLAC National Accelerator Laboratory) Alan Fisher (SLAC National Accelerator Laboratory)

Presentation materials

There are no materials yet.