Investigation of first mirror heating for the collective Thomson scattering diagnostic in ITER

Salewski, M.; Meo, F.; Bindslev, H.; Furtula, V.; Korsholm, S. B.; Lauritzen, B.; Leipold, F.; Michelsen, P. K.; Nielsen, S. K.; Nonbo\l, E.
October 2008
Review of Scientific Instruments;Oct2008, Vol. 79 Issue 10, p10E729
Academic Journal
Collective Thomson scattering (CTS) has the capabilities to measure phase space densities of fast ion populations in ITER resolved in configuration space, in velocity space, and in time. In the CTS system proposed for ITER, probing radiation at 60 GHz generated by two 1 MW gyrotrons is scattered in the plasma and collected by arrays of receivers. The transmission lines from the gyrotrons to the plasma and from the plasma to the receivers contain several quasioptical mirrors among other components. These are designed to produce astigmatic beam patterns in the plasma where the beam shapes will have a direct impact on the signal strength of the diagnostic, the spatial resolution, and the robustness of probe and receiver beam overlap against density excursions. The first mirror has a line of sight to the plasma and is thus exposed to severe neutron streaming. The present neutronics and thermomechanical modeling of a first mirror on the high field side indicates that the mirror curvature may warp due to heating. This may alter the beam quality, and therefore, thermal effects have to be accounted for during the design of the mirror. The modeling further demonstrates that thin mirrors are superior to thick mirrors from a thermomechanical point of view.


Related Articles

  • Development of gyrotrons for plasma diagnostics (invited). Woskoboinikow, P. // Review of Scientific Instruments;Aug1986, Vol. 57 Issue 8, p2113 

    Recent advances in high-frequency (> 100 GHz) gyrotron technology are reviewed and application to millimeter/submillimeter wave plasma diagnostics is discussed. Gyrotrons have useful capabilities of high-power (> 1 kW), long pulse/cw operation, narrow linewidth (< 100 kHz), and good spatial mode...

  • Characterization and preliminary results of the collective Thomson scattering system on FTU tokomak. Orsitto, F.; Brusadin, A.; Brodsky, Yu.; Filchenkov, S.; Grosso, G.; Giovannozzi, E.; Lubyako, L.; Perminov, A.; Suvorov, E.; Tartari, U.; Volpe, F. // Review of Scientific Instruments;Jan1999, Vol. 70 Issue 1, p1158 

    Discusses the characterization and preliminary results of the collective Thomsom scattering (CTS) system on FTU tokamak. Measurement of the plasma ion temperature and test of the theory of the CTS; Collection of scattered radiation; Antenna decoupling measurement; Detection of the ordinary...

  • Structures in T[sub e] profiles: High resolution Thomson scattering in the Rijnhuizen project. Beurskens, M.N.A.; Barth, C.J.; Lopes Cardozo, N.J.; van der Meiden, H.J. // Review of Scientific Instruments;Jan1999, Vol. 70 Issue 1, p995 

    Discusses typical examples of profile measurements obtained with the double pulse Thomson scattering diagnostic in the Rijnhuizen tokamak project. High spatial resolution enabling the measurement of small scale structures in T[sub e], n[sub e] and p[sub e]; Indication of the Thomson scattering...

  • Progress on the multipulse Thomson scattering diagnostic on DIII-D. Stockdale, R.E.; Carlstrom, T.N.; Hsieh, C.L.; Makariou, C.C. // Review of Scientific Instruments;Jan1995, Vol. 66 Issue 1, p490 

    Measures the DIII-D tokamak Thomson scattering diagnostic to measure electron temperature and density profiles throughout the plasma discharge. Progress enabling a new set of operating modes to better fulfill varying plasma physics requirements; Demonstration of two modes of operation.

  • Photon recycling system for multiposition tangential Thomson scattering. Barth, C.J.; Chu, C.C.; Donne, A.J.H. // Review of Scientific Instruments;Jan1995, Vol. 66 Issue 1, p501 

    Examines a multiposition tangential Thomson scattering to measure the profiles of the local drift velocity and current density of a tokamak plasma. High photon yield required to achieve a reasonably small observational error; Proposal of an optical system to increase the photon yield by a...

  • Modification of the collective Thomson scattering radiometer in the search for parametric decay on TEXTOR. Nielsen, S. K.; Salewski, M.; Bongers, W.; Korsholm, S. B.; Leipold, F.; Meo, F.; Michelsen, P.; Moseev, D.; Oosterbeek, J. W.; Stejner, M.; Westerhof, E. // Review of Scientific Instruments;Nov2012, Vol. 83 Issue 11, p113508 

    Strong scattering of high-power millimeter waves at 140 GHz has been shown to take place in heating and current-drive experiments at TEXTOR when a tearing mode is present in the plasma. The scattering signal is at present supposed to be generated by the parametric decay instability. Here we...

  • Thomson scattering system on FTU tokamak: Calibration, operation, results. Orsitto, F.; Brusadin, A.; Giovannozzi, E.; Santi, D.; Bartiromo, R.; Pizzolati, P. // Review of Scientific Instruments;Feb1995, Vol. 66 Issue 2, p1167 

    Reports on the use of the Frascati tokamak upgrade Thomson scattering system to measure the electron temperature and density spatial profiles along the vertical torus diameter in 19 spatial points up to ten times in a single plasma discharge with a spatial resolution ranging from two four...

  • Feasibility study of using the TFTR Thomson scattering system for q profile measurements. Brizard, A.; Grek, B.; Leblanc, B.; Johnson, D. // Review of Scientific Instruments;Aug1986, Vol. 57 Issue 8, p1813 

    The results of a study made to determine the possibility of using the tokamak fusion test reactor (TFTR) Thomson scattering system to measure the direction of the local magnetic fields in a tokamak plasma are presented. We find that it should be possible to measure the q profile for q < 1.3 and...

  • 10 kHz repetitive high-resolution TV Thomson scattering on TEXTOR. van der Meiden, H. J.; Barth, C. J.; Oyevaar, T.; Varshney, S. K.; DonnĂ©, A. J. H.; Kantor, M. Yu.; Kouprienko, D. V.; Alexeev, A.; Biel, W.; Pospieszczyk, A. // Review of Scientific Instruments;Oct2004 Part I & II, Vol. 75 Issue 10, p3849 

    In December 2003 a new 10 kHz multiposition Thomson scattering diagnostic with high spatial resolution has become operational on the TEXTOR tokamak. The system is the follow up of the high-resolution double-pulse Thomson scattering diagnostic. The conventional ruby laser has been replaced by a...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics