Low aspect ratio tokamaks (LATs) can potentially provide a high ratio
of plasma pressure to magnetic pressure beta and high plasma current I
at a modest size. This opens up the possibility of a high-power densi
ty compact fusion power plant. For the concept to be economically feas
ible, bootstrap current must be a major component of the plasma curren
t, which requires operating at high beta(p). A high value of the Troyo
n factor beta(N) and strong shaping is required to allow simultaneous
operation at a high-P and high bootstrap fraction. Ideal magnetohydrod
ynamic stability of a range of equilibria at aspect ratio 1.4 is syste
matically explored by varying the pressure profile and shape. The pres
sure and current profiles are constrained in such a way as to assure c
omplete bootstrap current alignment. Both beta(N) and beta are defined
in terms of the vacuum toroidal field. Equilibria with beta(N) greate
r than or equal to 8 and beta similar to 35%-55% exist that are stable
to n=infinity ballooning modes. The highest beta case is shown to be
stable to n=0,1,2,3 kink modes with a conducting wall. (C) 1997 Americ
an Institute of Physics.