PROGRESS IN IN THE PROJECT OF THE HIGH FIELD SIDE REFLECTOMETRY SYSTEM FOR THE MAIN PLASMA IN ITER V. A. Vershkov, D. A. Shelukhin, A. O. Urazbaev, V.A. Zhuravlev NFI FSI RRC “Kurchatov Institute”, , Moscow, Russian Federation

System characteristics requirements standard discharge scenario (Scen 2) It is possible to work on the high field side with: –Ordinary wave frequencies GHz –Extraodinary frequencies 8 – 78 GHz 1 – extraordinary wave (low frequency cut off) 2 – ordinary wave 3 – electro cyclotron frequency 4 – extraordinary wave (high frequency cut off) 5 – double electron cyclotron frequency

PROGRESS IN HFS ITER REFLECTOMETRY UP TO In 2005 the following works have been carried out: 1. The final version of the waveguides routes from antenna to the door to gallery were designed in form of CATIA models. 2. The works on construction of the laboratory test facility were continued. In particular the moke up of the two blanket modules were made and the optimized bends were manufacured. 3. The official cooperation between Kurchatov Institute and Institute of Applied Physics in Nijnii Novgorod started since June The goals - optimization of the bends and vacuum window.

4. Modification of 2D full-wave program for the Xl mode was in progress in This will increase it capabilities in calculation of propagation of Xl mode in turbulent plasma. 5. HFS reflectometry was recently installed in T-10 and tested on the turbulence measurements. 6. Neutron fluxes were estimated over the guide route and first 3D temperature estimations of the antenna heating were done 7. Semiconductor sweeeping frequency GANNs generators were purchased and tested in T The sweeping power supply was build and tested in T-10.

Schematics of combined horn/mirror antenna

Outline of the waveguide transmission line

The full-scale prototype of blanket section consisting of 2 modules with the gap in toroidal direction for test of passage of microwaves. Antennas prototypes are settled in the gap (right foto)

Hyperbolic secant R 0 =50 mm Req=58 mm Xl mode O mode

Hyperbolic secant R 0 =75 mm Req=87 mm Xl mode O mode

Hyperbolic secant R 0 =100 mm Req=116 mm Xl mode O mode

90 degree hyperbolic secant. What R is appropriate?? R 0 (mm)A(mm)B(mm)C(mm)

RUSSIAN RESEARCH CENTER “KURCHATOV INSTITUTE” HFS reflectometry system in T-10 First spectra from HFS Xl-mode reflectometry OH T-10 discharge Reflection at about a/2 Clearly seen poloidal turbulence rotation and MHD modes No Quasi-Coherent modes Very low frequency to reach the core plasma.

RUSSIAN RESEARCH CENTER “KURCHATOV INSTITUTE” HFS reflectometry system in T-10 High quality of the overall phase tracking Extremely low relative level of the fluctuations of the total signal The typical value 0.15 – 0.2 with the saturation limit of 1.5. It opens possibilities to work without saturation in strongly heated plasmas. Good tracking of the MHD events (sawtooth pfase jumps)

Comparison of reflectometry fluctuation spectra from the top and HFS in OH plasma

Comparison of radial profiles of the reflectometry turbulence fluctuation level from the top and HFS in OH and 1 MW ECRH

First experiments with the broad (28 – 32 GHz) fast (200  s) frequency scan at HFS in monostatic antenna variant

Schematics of the designed primary wacuum window VW was designed on the base of the ideas of paper of M. Petelin, W. Kasparek In Int. J.Electronics, 1991, Vol 71, # 5, 871 – The geometry and transmission was worked out during the contract of Kurchatov Institute with Nijnii Novgorod in 2005

Corrugated quartz vacuum window transmission for E parallel to the long waveguide side 1.VW was designed on the base of the ideas of paper Of M. Petelin, W. Kasparek In Int. J.Electronics, 1991, Vol 71, # 5, 871 – The geometry and transmission was worked out during the contract of Kurchatov Institute with Nijnii Novgorod in 2005

Corrugated vacuum window transmission for E perpendicular to the long waveguide side 1.VW was desined on the base of the ideas of paper Of M. Petelin, W. Kasparek In Int. J.Electronics, 1991, Vol 71, # 5, 871 – The geometry and transmission was worked out during the contract of Kurchatov Institute with Nijnii Novgorod in 2005

1. We made wide range of the 90 degree bends search in dimensions. We should choose the finite bend dimension, which is possible to use. What is the BIGGEST bend among 4 is appropriate? (This is also referred to 40 degree bend) 2. The small distance between waveguides make difficult to construct the horns. Is it possible to increase the distance between the waveguides by transferring some magnetics cables inside waveguides? Or to expand waveguides Just in vicinity of equatorial plane (less cabling?) 3. The minimal allowed gap between the blankets should be stated ALL THIS QUESTIONS SHOULD BE SETTLED IN 2006