Numerical modelling of the CEBAF electron gun with EGUN

Conference · Mon Sep 10 04:00:00 EDT 1990

OSTI ID:882528

Liger, Philippe; Krafft, Geoffrey

The electron source used in the injector for the CEBAF accelerator is a Hermosa electron gun with a 2 mm diameter cathode and a control electrode. It produces a 100 keV electron beam to be focused on the first of two apertures which comprise an emittance filter. A normalized emittance of less than {pi} mm mrad at 1.2 mA is set by the requirements of the final beam from the CEBAF linac, since downstream of the filter, a system of two choppers and a third aperture removes 5/6 of the current. In addition, for RF test purposes a higher current of about 5 mA is needed, possibly at higher emittance. This paper presents a way of calculating the characteristics of the CEBAF electron gun with the gun design code EGUN, and the accuracy of the results is discussed. The transverse shape of the beam delivered by the gun has been observed, and its current measured. A halo around the beam has been seen, and the calculations can reproduce this effect.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA
• Sponsoring Organization: USDOE - Office of Energy Research (ER)
• DOE Contract Number: AC05-84ER40150
• OSTI ID: 882528
• Report Number(s): CEBAF-PR-90-43; DOE/ER/40150-3887
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCURACY
APERTURES
CATHODES
CEBAF ACCELERATOR
DESIGN
ELECTRON BEAMS
ELECTRON GUNS
ELECTRON SOURCES
LINEAR ACCELERATORS
SHAPE
SIMULATION