ICRH physics and technology achievements in JET-ILW

ICRH was extensively used in the 2015-16 JET-ILW (ITER like wall) experimental campaign; bulk heating together with high-Z impurity chase-out from plasma centre importantly contributed to the good DD fusion performance obtained recently in JET. Power up to 6 MW was launched in H-mode deuterium plasmas and 8 MW during the hydrogen campaign. The ILA was re-installed and contributed positively to the availability of ICRH power. The ILA produces slightly less high-Z impurities than the A2's and the PWI measured via Be line emission on limiters is in the same ballpark. Specific experiments were conducted to optimise ICRH scenarios in preparation for DT in particular the dual frequency scheme, (H)D and (He)D were tested. In addition, it was confirmed that the (D)H scenario is accessible in a ILW environment and the novel 3-ions ICRH scheme was validated experimentally.

[1]  D. Coster,et al.  3D simulations of gas puff effects on edge plasma and ICRF coupling in JET , 2017 .

[2]  J. Stober,et al.  A comparison of the impact of central ECRH and central ICRH on the tungsten behaviour in ASDEX Upgrade H-mode plasmas , 2017 .

[3]  J. Contributors,et al.  Ion cyclotron resonance heating for tungsten control in various JET H-mode scenarios , 2017 .

[4]  D. Coster,et al.  Modelling of the ICRF induced E  ×  B convection in the scrape-off-layer of ASDEX Upgrade , 2016 .

[5]  R. I. Pinsker,et al.  Maximization of ICRF power by SOL density tailoring with local gas injection , 2016 .

[6]  C. Giroud,et al.  Optimization of ICRH for core impurity control in JET-ILW , 2016 .

[7]  J. Contributors,et al.  N=2 ICRH of H majority plasmas in JET-ILW , 2015 .

[8]  J. Contributors,et al.  Impact of localized gas injection on ICRF coupling and SOL parameters in JET-ILW H-mode plasmas , 2015 .

[9]  J. Contributors,et al.  Localized Scrape-Off Layer density modifications by Ion Cyclotron near fields in JET and ASDEX-Upgrade L-mode plasmas , 2015 .

[10]  F Durodie,et al.  Design and operations of a load-tolerant external conjugate-T matching system for the A2 ICRH antennas at JET , 2013, 1309.4644.

[11]  R. Neu,et al.  ICRF specific plasma wall interactions in JET with the ITER-like wall , 2013 .

[12]  Julien Hillairet,et al.  Self consistent radio-frequency wave propagation and peripheral direct current plasma biasing: Simplified three dimensional non-linear treatment in the 'wide sheath' asymptotic regime , 2012 .

[13]  O. Meneghini,et al.  A multi-cavity approach for enhanced efficiency in TOPICA RF antenna code , 2009 .

[14]  R. Felton,et al.  Hydrogen plasmas with ICRF inverted minority and mode conversion heating regimes in the JET tokamak , 2006 .

[15]  L. Colas,et al.  Edge plasma density convection during ion cyclotron resonance heating on Tore Supra , 2002 .

[16]  F. W. Perkins,et al.  Radiofrequency sheaths and impurity generation by ICRF antennas , 1989 .