ECR4-14 GHZ :
The ion source is optimized on 40Ar9+ (black spectrum). This is a reference spectrum with 160 µA of Ar9+. After a plasma chamber replacement, the ion source is validated if the Ar9+ beam intensity is greater or equal to 120 µA. A record intensity of 245 µA has been reported on the graph below (red spectrum) although no clear conclusion could be made : much better distribution due to a magnesium wall coating effect, or due to the higher RF power injected into the plasma ?
Phoenix V2 - 18 GHz :
2012-02-24 15:25. Best spectrum obtained at LPSC-Grenoble equiped with the SPIRAL 2 beam line, optomized on 40Ar14+. RF power 1.63kW (69 reflected), Source voltage 60.0kV/6.3mA, biased disk : 53V/0.3mA, buffer gaz O2, ext. pressure 2.1E8mbaroptimisé 40Ar14+ : 48 µA. P_HF : 1.63 kW, P_HF_réf : 69 W, HT_S : 60.0 kV lu / 12.9 mA (~ 6.3 mA réel), Biased disk : -53 V / 0.3 mA, gaz support O2 : 7.21 V, p_ext : 2.1E-8 mbar, four : court-circuité en position zéro, BPI-BPM-BPE cons : 1194 A / 1117 A / 1247 A, BPI-BPM-BPE lu : 1096 A / 1116 A / 1250 A, Optique cons : SOL11 : 167.4 A, D11 : 78.06 A, Q11 : 24.06, Q12 : 49.40 A, Q13 : 64.50 A, tout le reste à zéro, RPE : 2.0 kV , 4.2 mA (un peu en court-circuit).