1. Studies on fast ion distribution Correlated with the spectroscopy diagnostics measurements Gerarda Apruzzese http://www.afs.enea.it/apruzzes/ CRE Frascati - ENEA Culham, July the 24th

2. Aim of this work Analysis of the positive and negative aspects of the diagnostics using the CX spectrum and their possible development at JET

3. Diagnostics compared in the analysis the diagnostic FIDA developed in DIII-D W.W.Heidbrink et al., PPCF 49, (2007) 1457-1475 the fast ion CXRS diagnostic developed in Textor Proceedings of the 17 th Topical Conference on High- Temperature Plasma Diagnostics, Albuquerque, New Mexico, May 2008

4. FIDA Diagnostic ( Fast Ion D  Analysis) Measurement of the vertical component of perpendicular energy CX emission spectrum of re-neutrals generated by beam: CX ( beam - plasma ions) fast ions CX ( fast ions – beam ) re-neutrals

5. FIDA measurements in DIII-D Successful on DIII-D in detecting both NB and ICRH accelerated D Y.Luo and W.W. Heidbrink, RSI 78, 033505 (2007)

6. For FIDA success it is necessary Vertical views ( Doppler shift only due to gyromotion of fast ions) Good hardware ( f# of spectrometer, detector, system for avoiding detector saturation) Beam modulation ( for subtracting the background)

7. Complications of FIDA The extracted signal is 10 times less the detected signal so GOOD HARDWARE and APPROPRIATE OPTICAL VIEW are required Spectral overlap with BES spectrum Intense cold Dalpha light Halo (from CX plasma-beam)

8. The fast ion CXRS diagnostic Using the Fokker-Plank code to simulate the D  beam emission spectrum Good results on Textor, where a favourable viewing geometry permits to separate the contributions due to the fast ions and the beam emission spectrum (BES)

9. CX measurements at TEXTOR Red wing (BES) Blu wing (slowing down) spectrum simulation

10. Situation at JET First and preliminary analysis done by von Hellermann and Delabie using the technique of fast ion CX diagnostic. Good results. http://users.jet.efda.org/pages/d-task-force/meetings/2008/080626/Delabie.ppt FIDA diagnostic requires a vertical viewing line avoiding the divertor region (characterised by strong emission) and dedicated equipment.

11. Next step for FIDA : firstly, check of vertical view for fast ion CX : –Prepare future upgrading of spectrometer (Textor group) –Extend the simulation modelling in order to include effects of instabilities on slowing down distribution function (Frascati and Textor groups)