Generalized scaling laws for the formation of plasma confiningpotentials and the associated effectiveness of the potentials produced aresystematically investigated to find the physics essentials common to therepresentative tandem mirror operational modes of GAMMA 10, and toexplore novel extended operational modes from the scaling bases constructed.(a) The potential formation scalings are generalized using a novel finding ofwider validity of Cohen's strong ECH theorycovering the representative modes. (b) The potentials produced, in turn,provide a favourable novel scaling of the increase in the central cell electrontemperatures Te with increasing thermal barrier potentials ϕb, limited by theavailable ECH power. The scaling of Te with ϕb is well interpreted in terms ofthe generalized Pastukhov theory of plasma potential confinement. A detailedcomparison of the results from several related modified theories is also made.(c) Consolidation of the two major scalings of (a) and (b) in a tandem mirror iscarried out by the use of an electron energy balance equation for the first time.In addition, (d) an empirical scaling of ϕc with ECH power in the plug regionand the central cell densities are studied to discover whether there is the possibility of extending these theoretically well interpreted scaling data to parametersin the future scalable regime. There is also a discussion about numerical scalings in thethree dimensional parameter spaces.
Study of near SOL decay lengths in ASDEX Upgrade under attached and detached divertor conditions