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Scalings and Plasma Profile Parameterisation of ASDEX High Density Ohmic Discharges

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 نشر من قبل Kurt Riedel
 تاريخ النشر 2018
  مجال البحث فيزياء
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High density ($.3 < bar{n}/10^{20}{rm m^{-3}} < .8$), low $q_a$ ($1.9<q_a<3.4$), Ohmic discharges from the ASDEX experiment is analysed statistically. Bulk parameter scalings and parameterised temperature and density profile shapes are presented. The total plasma kinetic energy, assuming $T_i=T_e$, scales as $bar{n}^{ .54pm .01} {I_p}^{.90pm .04 } $ and is almost independent of $B_t$. The electron temperature profile peaking factor scales as ${T_0^{3/2}/<T^{3/2}>} = .94(pm.04){q_a}^{1.07pm.04}$ in close agreement with the assumption of classical resistive equilibrium. In the inner half of the plasma, the inverse fall-off length for both temperature and density has a strong dependence on $q_a$, with the temperature dependence being more pronounced. Outside the half radius, the $q_a$ dependence disappears but the density profile broadens near the edge with increasing plasma current.



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