skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Development of an X-band magnicon amplifier for the Next Linear Collider -- Cold cathode experiments and a thermionic design study

Abstract

The Naval Research Laboratory has been studying the operation of an 11 GHz frequency-doubling magnicon amplifier driven by a {approximately}650 kV, 225 A, 5.5-mm-diam. electron beam produced by a velvet cathode driven by a single-shot Marx generator. Recent experiments using a heterodyne diagnostic have demonstrated emission at 11.12 GHz, the predicted magnicon output frequency, in a 200 nsec pulse when the first cavity is driven at 5.56 GHz. Under these conditions, the experiment produced {approximately} 15 MW at {approximately} 10% efficiency. Simulations suggest that this low efficiency is due to operation in a regime in which all of the spin up occurs in the penultimate deflection cavity, and also to the large beam diameter. Based on these results, it became evident that the NRL program must transition to a thermionic electron gun, a rep-rated modulator, and an ultrahigh vacuum environment in order to demonstrate the feasibility of an efficient, long-pulse, high-duty-factor magnicon amplifier at 11.4 GHz for linear accelerator applications. The authors have designed a new thermionic magnicon experiment, incorporating an advanced high-convergence electron gun to produce a 500 kV, 200 A, 2-mm-diam. electron beam, an improved deflection cavity design, and an improved output cavity that employs side-coupling to extractmore » the rf power through a pair of X-band waveguides separated by 135{degree} around the azimuth of the cavity without destroying the symmetry of the rotating quadrupole mode. The predicted efficiency is {approximately} 60%.« less

Authors:
;  [1];  [2];  [3]; ;  [4];  [5]
  1. Naval Research Lab., Washington, DC (United States). Plasma Physics Div.
  2. Icarus Research, Bethesda, MD (United States)
  3. SFA, Landover, MD (United States)
  4. Budker Inst. of Nuclear Physics, Novosibirsk (Russian Federation)
  5. Litton Systems, Inc., San Carlos, CA (United States). Electron Devices Div.
Publication Date:
Sponsoring Org.:
USDOE, Washington, DC (United States); Department of the Navy, Washington, DC (United States)
OSTI Identifier:
445555
Report Number(s):
CONF-960634-
Journal ID: ISSN 0730-9244; TRN: 97:005184
Resource Type:
Conference
Resource Relation:
Conference: 1996 IEEE international conference on plasma science, Boston, MA (United States), 3-5 Jun 1996; Other Information: PBD: 1996; Related Information: Is Part Of IEEE conference record -- Abstracts: 1996 IEEE international conference on plasma science; PB: 324 p.
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; LINEAR COLLIDERS; MICROWAVE AMPLIFIERS; PERFORMANCE; ELECTRON GUNS; THERMIONIC EMISSION; DESIGN

Citation Formats

Gold, S H, Fliflet, A W, Hafizi, B, Kinkead, A K, Nezhevenko, O A, Yakovlev, V P, and True, R B. Development of an X-band magnicon amplifier for the Next Linear Collider -- Cold cathode experiments and a thermionic design study. United States: N. p., 1996. Web.
Gold, S H, Fliflet, A W, Hafizi, B, Kinkead, A K, Nezhevenko, O A, Yakovlev, V P, & True, R B. Development of an X-band magnicon amplifier for the Next Linear Collider -- Cold cathode experiments and a thermionic design study. United States.
Gold, S H, Fliflet, A W, Hafizi, B, Kinkead, A K, Nezhevenko, O A, Yakovlev, V P, and True, R B. Tue . "Development of an X-band magnicon amplifier for the Next Linear Collider -- Cold cathode experiments and a thermionic design study". United States.
@article{osti_445555,
title = {Development of an X-band magnicon amplifier for the Next Linear Collider -- Cold cathode experiments and a thermionic design study},
author = {Gold, S H and Fliflet, A W and Hafizi, B and Kinkead, A K and Nezhevenko, O A and Yakovlev, V P and True, R B},
abstractNote = {The Naval Research Laboratory has been studying the operation of an 11 GHz frequency-doubling magnicon amplifier driven by a {approximately}650 kV, 225 A, 5.5-mm-diam. electron beam produced by a velvet cathode driven by a single-shot Marx generator. Recent experiments using a heterodyne diagnostic have demonstrated emission at 11.12 GHz, the predicted magnicon output frequency, in a 200 nsec pulse when the first cavity is driven at 5.56 GHz. Under these conditions, the experiment produced {approximately} 15 MW at {approximately} 10% efficiency. Simulations suggest that this low efficiency is due to operation in a regime in which all of the spin up occurs in the penultimate deflection cavity, and also to the large beam diameter. Based on these results, it became evident that the NRL program must transition to a thermionic electron gun, a rep-rated modulator, and an ultrahigh vacuum environment in order to demonstrate the feasibility of an efficient, long-pulse, high-duty-factor magnicon amplifier at 11.4 GHz for linear accelerator applications. The authors have designed a new thermionic magnicon experiment, incorporating an advanced high-convergence electron gun to produce a 500 kV, 200 A, 2-mm-diam. electron beam, an improved deflection cavity design, and an improved output cavity that employs side-coupling to extract the rf power through a pair of X-band waveguides separated by 135{degree} around the azimuth of the cavity without destroying the symmetry of the rotating quadrupole mode. The predicted efficiency is {approximately} 60%.},
doi = {},
journal = {},
issn = {0730-9244},
number = ,
volume = ,
place = {United States},
year = {1996},
month = {12}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share: