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Abstract. The UCLA Electric Tokamak (ET), a low field ITER sized device,
has been operating with well equilibrated clean plasmas since January 2000.
The operating scenario is still evolving as the magnetic configuration and
the power supplies undergo refinements. The goal of equilibrating near unity
beta plasmas will require 10 second long discharges at 3 kV temperatures in
a toroidal field of 0.25 Tesla due to current shaping requirements. Short,
0.9 sec, discharges are now routinely obtained with
kTe, kTi 
120eV at a toroidal field of 0.1 Tesla. The discharges are feedback controlled
in up/down position and in plasma current. Biased electrode driven H-modes
have been obtained and compare well to the results obtained on CCT and to
the ``neoclassical bifurcation'' theory. Very successful second harmonic ion
heating has been demonstrated with an ICRF antenna outside of the vacuum
system and 50% single pass absorption. These discharges also indicate that
edge bifurcation can be achieved by RF alone due to fast ion losses. The
remaining critical item needed for the exploration of unity beta plasma
stability is the demonstration of RF current profile shaping near the Troyon
limit. We expect that ion-ion hybrid mode conversion (high field side
launch) will allow current drive at low beta. This can then be supplemented
by high harmonic current drive at higher beta. Ultimately, near ignition
conditions could be reached if magnetic omnigeneity (classical transport
physics) were obtained at a toroidal field of 1 Tesla. The test of this
concept is to be carried out at 0.25 Tesla in the coming year, if RF current
profile shaping can be achieved and supplemented by bootstrap and diffusion
driven current.
IAEA 2001
