3
Improved
Magnetron Injection Guns for Gyrotrons--Calabazas Creek Research, 20937 Comer Drive,
Saratoga, CA 95070-3753;
650-595-2168, www.calcreek.com
Dr.
R. Lawrence Ives, Principal Investigator, rlives@calcreek.com
Dr. Purobi Phillips, Business Official, purobi@calcreek.com
DOE
Grant No. DE-FG02-04ER83918
Amount:
$100,000
Gyrotrons
and gyroklystrons, used for high power radio frequency applications in the DOE
Fusion program, are being adversely impacted by poorly performing cathodes for
which the current emission is not uniform over the entire surface. This
results in a reduced operating efficiency along with excessive power densities
in the spent beam collector. This
project will determine the causes of emission non-uniformity and develop
cost-effective, uniformly emitting cathodes for improved performance.
Both temperature and work function issues will be addressed, as well as
improvements in electron gun design and cathode manufacture.
In Phase I, an existing test facility will be modified to incorporate
infrared temperature measurements, so that the relative impact of temperature
and work function can be determined. This
information, along with simulations using two- and three dimensional
thermomechanical and beam optics tools, will be used to evaluate the impact of
changes in cathode materials, mechanical and geometrical variations, and
modifications to manufacturing processes and procedures.
Commercial Applications and Other Benefits as described by the awardee: Increased gyrotron performance should impact several applications, including electron cyclotron heating, current drive, and the control of instabilities in fusion plasmas. Gyrotron cost reduction also would enable these devices to be used in other applications, including industrial heating and defense systems.