Neon Puffing Experiments in the JIPP T-IIU Tokamak

摘要

Large amounts of neon were puffed into the discharge of the JIPP T-IIU tokamak, producing values of effective ion charge, Z sub eff, as large as 6 or 7 at linear average electron density bar n sub e, up to 3.5 x 10 to the 13th/cu cm. Electron temperatures, T sub e, rise to about twice those obtained in hydrogen puffing discharges that have the same current and electron density time behavior. Energy containment times are about the same for the neon and hydrogen puffing cases. At high values of Z sub eff, there appears to be a difference between the value of Z sub eff calculated from the bar n sub e produced by neon puffing and the values calculated from Spitzer conductivity corrected for trapped electron effects. Brightness of Ne V, VIII, and IX lines and total radiated power were calculated from temperature and density profiles and the estimated amount of neon in the discharge. These calculations agree well with measured values, except at the highest values of bar n sub e and Z sub eff, where the calculated power is twice measured.