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Title: Performance of a first generation X-band photoelectron rf gun

Journal Article · · Physical Review Accelerators and Beams
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Building more compact accelerators to deliver high brightness electron beams for the generation of high flux, highly coherent radiation is a priority for the photon science community. A relatively straightforward reduction in footprint can be achieved by using high-gradient X-band (11.4 GHz) rf technology. To this end, an X-band injector consisting of a 5.5 cell rf gun and a 1-m long linac has been commissioned at SLAC. It delivers an 85 MeV electron beam with peak brightness somewhat better than that achieved in S-band photoinjectors, such as the one developed for the Linac Coherent Light Source (LCLS). The X-band rf gun operates with up to a 200 MV/m peak field on the cathode, and has been used to produce bunches of a few pC to 1.2 nC in charge. Notably, bunch lengths as short as 120 fs rms have been measured for charges of 5 pC (~3×107 electrons), and normalized transverse emittances as small as 0.22 mm-mrad have been measured for this same charge level. Bunch lengths as short as 400 (250) fs rms have been achieved for electron bunches of 100 (20) pC with transverse normalized emittances of 0.7 (0.35) mm-mrad. As a result, we report on the performance and the lessons learned from the operation and optimization of this first generation X-band gun.

Research Organization:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
Grant/Contract Number:
AC02-76SF00515
OSTI ID:
1251016
Alternate ID(s):
OSTI ID: 1251380
Journal Information:
Physical Review Accelerators and Beams, Vol. 19, Issue 5; ISSN 2469-9888
Publisher:
American Physical SocietyCopyright Statement
Country of Publication:
United States
Language:
English

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