Vacuum ultraviolet impurity spectroscopy on the Alcator C-Mod tokamak

Reinke, M. L.; Beiersdorfer, P.; Howard, N. T.; Magee, E. W.; Podpaly, Y.; Rice, J. E.; Terry, J. L.
October 2010
Review of Scientific Instruments;Oct2010, Vol. 81 Issue 10, p10D736
Academic Journal
Vacuum ultraviolet spectroscopy is used on the Alcator C-Mod tokamak to study the physics of impurity transport and provide feedback on impurity levels to assist experimental operations. Sputtering from C-Mod's all metal (Mo+W) plasma facing components and ion cyclotron range of frequency antenna and vessel structures (sources for Ti, Fe, Cu, and Ni), the use of boronization for plasma surface conditioning and Ar, Ne, or N2 gas seeding combine to provide a wealth of spectroscopic data from low-Z to high-Z. Recently, a laser blow-off impurity injector has been added, employing CaF2 to study core and edge impurity transport. One of the primary tools used to monitor the impurities is a 2.2 m Rowland circle spectrometer utilizing a Reticon array fiber coupled to a microchannel plate. With a 600 lines/mm grating the 80<λ<1050 Å range can be scanned, although only 40-100 Å can be observed for a single discharge. Recently, a flat-field grating spectrometer was installed which utilizes a varied line spacing grating to image the spectrum to a soft x-ray sensitive Princeton Instruments charge-coupled device camera. Using a 2400 lines/mm grating, the 10<λ<70 Å range can be scanned with 5-6 nm observed for a single discharge. A variety of results from recent experiments are shown that highlight the capability to track a wide range of impurities.


Related Articles

  • Development of two-grating spectrometer for the charge exchange spectroscopy system on KSTAR. Lee, Hyungho; Song, Eun-ji; Park, Young-dong; Oh, Soo-ghee; Ko, Won-Ha // Review of Scientific Instruments;Jun2011, Vol. 82 Issue 6, p063510 

    The charge exchange spectroscopy (CES) system on Korea Superconducting Tokamak Advanced Research (KSTAR) was installed last year and had been applied to measure the C VI ion temperature and rotation velocity profiles. The ion temperature and rotation velocity profiles had been estimated from the...

  • Optical diagnostic to measure ion temperature and parallel velocity fluctuations on the Tokamak... Evensen, H.T.; Durst, R.; Fonck, R.J.; Paul, S.F. // Review of Scientific Instruments;Jan1995, Vol. 66 Issue 1, p845 

    Develops a high-frequency charge exchange recombination spectroscopy diagnostic (HF-CHERS) to give localized measurements of ion temperature and parallel velocity microturbulence in the plasma core of the Tokamak Fusion Test Reactor (TFTR). Interference filter spectrometer used in the HF-CHERS;...

  • Very high spectral resolution obtained with SU5: A vacuum ultraviolet undulator-based beamline at Super-ACO. Nahon, Laurent; Alcaraz, Christian; Marlats, Jean-Louis; Lagarde, Bruno; Polack, Franc¸ois; Thissen, Roland; Lepere, Didier; Ito, Kenji // Review of Scientific Instruments;Feb2001, Vol. 72 Issue 2, p1320 

    In this article we wish to report on the commissioning of the SU5 undulator-based beamline, whose primary scientific goal deals with high-resolution spectroscopy and photon-induced dynamics in the vacuum ultraviolet range on dilute species. In order to achieve such a scientific program, we have...

  • Measurements of nonthermal confined alpha particles in Tokamak Fusion Test Reactor D-T plasmas (invited) Stratton, B.C.; Budny, R. V.; Duong, H. H.; Mansfield, D. K.; Medley, S.S.; Redi, M. H.; Fonck, R. J.; McKee, G. R.; Odblom, A.; Wising, F.; Fisher, R. K.; McChesney, J. M.; Parks, P. B.; Petrov, M.P.; Gorelenkov, N. N. // Review of Scientific Instruments;Jan1997, Vol. 68 Issue 1, p269 

    Presents a summary of the experience with the alpha charge exchange recombination spectroscopy (alpha-CHERS) and pellet charge exchange confined, nonthermal alpha particle diagnostics over the first two years of Tokamak test fusion reactor D-T operation. Concept, instrumentation and analysis of...

  • Improvements in the CHERS system for DT experiments on TFTR. Bush, C.E.; Bell, R.E.; Synakowski, E.J. // Review of Scientific Instruments;Feb1995, Vol. 66 Issue 2, p1193 

    Describes modifications made to the charge exchange recombination spectroscopy (CHERS) system for deuterium/tritium experiments on the tokamak fusion test reactor. Structure of the CHERS system; Relocation of the spectrometer, the photon/neutron sensitive diode array, and all electronics;...

  • High time resolution ion temperature profile measurements on PBX. Gammel, G.; Kaita, R.; Fonck, R.; Jaehnig, K.; Powell, E. // Review of Scientific Instruments;Aug1986, Vol. 57 Issue 8, p1800 

    Ion temperature profiles with a time resolution of 2-5 ms have been measured on the Princeton Beta Experiment tokamak (PBX) by charge-exchange recombination spectroscopy (CXRS) and a neutral, particle charge-exchange analyzer (NPA). The sightlines of both diagnostics crossed the trajectory of a...

  • On the Spectra Selectivity of Talbot and Lau Effects. Lokshin, G. R.; Uchenov, A. V.; �ntin, M. A.; Belonuchkin, V. E.; Eskin, N. I. // Optics & Spectroscopy;Aug2000, Vol. 89 Issue 2, p312 

    The locations of self-reproduction planes in the Talbot effect and the distance between coherence peaks in the Lau effect are functions of the radiation wavelength. This fact can be used to develop new methods for spectral investigations. Below, we estimate the spectral selectivity of Talbot and...

  • Spectral observations of galaxies with UV excess. Karapetyan, E. // Astrophysics;Jul2006, Vol. 49 Issue 3, p299 

    Spectral observations of 19 galaxies with UV-excesses from Kazarian’s list are reported. The spectra were obtained with the 2.6-m telescope at the Byurakan Observatory using the SCORPIO spectral camera. A grism was used to obtain spectra in the wavelength interval λλ7420-3920 Å....

  • Super-broadband continuum generation with transient self-focusing of a terawatt laser pulse in rare gases. Nishioka, H.; Ueda, K.-I. // Applied Physics B: Lasers & Optics;Sep2003, Vol. 77 Issue 2/3, p171 

    Describes the generation of hype-continuum that continuously covers from the vacuum ultraviolet (VUV) to the infrared (IR) spectral regions with a flat spectral shape in nonlinear propagation in rare gases. Spectral intensity; Conversion efficiency; Spectral, spatial and temporal...


Read the Article


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

Try another library?
Sign out of this library

Other Topics