| dc.description.abstract | Los Alamos is investigating a number of high power
microwave (RPM) sources for their potential to power
advanced accelerators. Included in this investigation are the
large orbit gyrotron amplifier• and oscillator (LOG) arid the
relativistic klystron amplifier (RKA). LOG amplifier
development is newly underway. Electron beam power
levels of 3 OW, 70 ns duration, are planned, with anticipated
conversion efficiencies into RF on the :order of 20 percent.
Ongoing investigations on this device include experimental
improvement of the electron beam optics (to allow injection
of a suitable fraction of the electron beam born• in the gun
into the amplifier structure), and computational studies of
resonator design and RF extraction. Recent RKA studies
have. operated at electron beam powers into the device of
1.35 GW in microsecond duration pulses. The device has
yielded modulatt',(l electron beam power approaching 300
MW using 3-5 kW of RF input drive. RF powers extracted
into waveguide have been up to 70 MW, suggesting that
more power is available from the device than we have
converted to-date in the extractor. We have examined
several aspects of operation, including beam bunching
phenomena and RF power extraction techniques. In
addition, investigations of the amplifier gain as a function of
input drive, electron beam parameters (energy, current, and
position in the device) and axial magnetic field strength also
have been explored. The effect of ions formed during device
operation also has been considered. | en_US |
