Generalization and consolidation of scaling laws of potential formation and associated effects in the GAMMA 10 tandem mirror

Cho, T Hirata, M Hojo, H Ichimura, M Ishii, K Itakura, A Katanuma, I Kohagura, J Nakashima, Y Saito, T Tanaka, S Tatematsu, Y Yoshikawa, M Numakura, T Minami, R Nagashima, S Watanabe, H Yoshida, M Sakamoto, Y Tamano, T Yatsu, K Miyoshi, S

T. Cho et al., Generalization and consolidation of scaling laws of potential formation and associated effects in the GAMMA 10 tandem mirror, NUCL FUSION, 41(9), 2001, pp. 1161-1170

36

INGLESE

Article

Physics

NUCLEAR FUSION

0029-5515 → ACNP

41

9

2001

1161 - 1170

ISI

0029-5515(200109)41:9<1161:GACOSL>2.0.ZU;2-E

Generalized scaling laws for the formation of plasma confining potentials a nd the associated effectiveness of the potentials produced are systematical ly investigated to find the physics essentials common to the representative tandem mirror operational modes of GAMMA 10, and to explore novel extended operational modes from the scaling bases constructed. (a) The potential fo rmation scalings are generalized using a novel finding of wider validity of Cohen's strong ECH theory covering the representative modes. (b) The poten tials produced, in turn, provide a favourable novel scaling of the increase in the central cell electron temperatures T-e with increasing thermal barr ier Potentials phi (b), limited by the available ECH power. The scaling of T-e with phi (b) is well interpreted in terms of the generalized Pastukhov theory of plasma potential confinement. A detailed comparison of the result s from several related modified theories is also made. (c) Consolidation of the two major scalings of (a) and (b) in a tandem mirror is carried out by the use of an electron energy balance equation for the first time. In addi tion, (d) an empirical scaling of phi (c) with ECH power in the plug region and the central cell densities are studied to discover whether there is th e possibility of extending these theoretically well interpreted scaling dat a to parameters in the future scalable regime. There is also a discussion a bout numerical scalings in the three dimensional parameter spaces.