Design of a {open_quotes}slow-wave{close_quotes} ubitron

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:238820

Pershing, D E; Jackson, R H; Freund, H P ^[1]

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1. Naval Research Lab., Washington, DC (United States); and others

The NRL fundamental TE{sub 11} mode ubitron has been successful in demonstrating high gain (29 dB large signal), broad instantaneous bandwidth (>20 %), high power (>4 MW), and efficient (18%) amplification in K{sub u} band with a 245 kV, 94 A beam. For a second generation ubitron amplifier design, it is desired to operate at higher frequencies and lower voltages, while preserving the gain, power, and bandwidth characteristics measured with the K{sub u} band amplifier. A K{sub a} band ubitron amplifier is currently under development utilizing the basic design concepts of the K{sub a} band amplifier: grazing intersection for wide instantaneous bandwidth, circularly polarized wiggler and microwave fields for high gain and power, and a high quality Pierce gun generating a cylindrical, uniform density electron beam for high efficiency. As has been previously demonstrated, the dispersion characteristics of a periodic waveguide can be exploited for low voltage FEL operation. This is the major point of departure from the K{sub u} band design; operation in the HE{sub 11} mode of corrugated cylindrical waveguide which permits broader bandwidth amplification at lower voltages than is possible with smooth waveguide. Preliminary calculations indicate that 30 % bandwidth operation in K{sub a} band is possible at voltages less than 150 kV with a 8-9 mm period wiggler. Design details and performance calculations will be presented.

• Research Organization: Brookhaven National Lab., Upton, NY (United States)
• OSTI ID: 238820
• Report Number(s): BNL--61982-Absts.; CONF-9508156--Absts.; ON: DE96002729
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
43 PARTICLE ACCELERATORS
DESIGN
ELECTRON BEAMS
FREE ELECTRON LASERS
POWER AMPLIFIERS
WIGGLER MAGNETS