Stability analysis of advanced regime tokamaks is presented. Here advanced regimes are defined to include configurations where the ratio of the bootstrap current,IBS, to the total plasma current,Ip, approaches unity, and the normalized stored energy, bgr;Nast;= 80pgr;lang;p2rang;1/2a/IpB0, has a value greater than 4.5. Here,pis the plasma pressure,athe minor radius in meters,Ipis in megahyphen;amps,B0is the magnetic field in Tesla, and lang;sdot;rang; represents a volume average. Specific scenarios are discussed in the context of Toroidal Physics Experiment (TPX) lsqb;Proceedingsofthe20thEuropeanPhysicalSocietyConferenceonControlledFusionandPlasmaPhysics, Lisbon, 1993, edited by J. A. Costa Cabral, M. E. Manso, F. M. Serra, and F. C. Schuller (European Physical Society, Petithyphen;Lancy, 1993), p. Ihyphen;80rsqb;. The best scenario is one with reversed shear, in theqprofile, in the central region of the tokamak. The bootstrap current obtained from the plasma profiles provides 90percnt; of the required current, and is well aligned with the optimal current profile for ideal magnetohydrodynamic stability. This configuration is stable up to bgr;Nast;ape; 6.8, if the external boundary conditions are relaxed to those corresponding to an ideal structure at a moderate distance of approximately 1.3 times the minor radius.
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