Plasma and Fusion Research

Volume 13, 3402020 (2018)

Regular Articles


Observation of Tungsten Line Emissions in Wavelength Range of 10 – 500 Å in Large Helical Device
Yang LIU1), Shigeru MORITA1,2), Tetsutarou OISHI1,2), Motoshi GOTO1,2) and Xianli HUANG2)
1)
Department of Fusion Science, Graduate University for Advanced Studies, Toki, Gifu 509-5292, Japan
2)
National Institute for Fusion Science, Toki, Gifu 509-5292, Japan
(Received 28 December 2017 / Accepted 19 February 2018 / Published 10 April 2018)

Abstract

Tungsten spectra have been observed in Large Helical Device (LHD) by injecting a coaxial tungsten pellet to identify the emission lines in extreme ultraviolet (EUV) range of 10 - 500 Å. The spectra of line emissions from tungsten ions have been measured in neutral-beam-heated discharges using two EUV spectrometers of EUV_Short and EUV_Long working in wavelength ranges of 10 - 130 Å and 50 - 500 Å, respectively. As a result, a lot of tungsten lines from low-ionized ions of W4+, W6+ and W7+ are observed for the first time in the toroidal device in addition to tungsten lines from highly ionized ions of W41+-W45+. Measured line emissions are carefully identified based on the NIST database and the determined wavelengths show a good agreement with the NIST database. The result is summarized in table with information on blended lines obtained from the radial profile measurement.


Keywords

tungsten spectra, extreme ultraviolet, spectrometer, pellet injection, Large Helical Device

DOI: 10.1585/pfr.13.3402020


References

  • [1] R. Neu et al., Nucl. Fusion 45, 209 (2005).
  • [2] J. Roth et al., Plasma Phys. Control. Fusion 50, 103001 (2008).
  • [3] J.W. Coenen et al., J. Nucl. Mater. 463, 78 (2015).
  • [4] A. Geier, H. Maier and R. Neu, Plasma Phys. Control. Fusion 44, 2091 (2002).
  • [5] R. Dux et al., J. Nucl. Mater. 390-391, 858 (2009).
  • [6] G.J. Van Rooij et al., J. Nucl. Mater. 438, S42 (2013).
  • [7] T. Oishi, S. Morita, X. Huang, H. Zhang, M. Goto and the LHD Experimental Group, Phys. Scr. 91, 025602 (2016).
  • [8] S. Morita et al., AIP Conf. Proc. 1545, 143 (2013).
  • [9] T. Nakano and the JT-60 Team, J. Nucl. Mater. 415, S327 (2011).
  • [10] R. Barnsley, the Decennial IAEA Technical Meeting on Atomic, Molecular and Plasma-Material Interaction Data for Fusion Science and Technology, Daejeon, South Korea, December 2014. https://www-amdis.iaea.org/meetings/AMPMI14/Presentations/AMPMI-2014-12-15-Talk-Barnsley-ITER-2by4.pdf
  • [11] X. Huang, S. Morita, T. Oishi, M. Goto and H. Zhang, Rev. Sci. Instrum. 85, 11E818 (2014).
  • [12] M.B. Chowdhuri, S. Morita and M. Goto, Appl. Opt. 47, 135 (2008).
  • [13] M.B. Chowdhuri, S. Morita and M. Goto, Rev. Sci. Instrum. 78, 023501 (2007).
  • [14] C. Dong, S. Morita, M. Goto and H. Zhou, Rev. Sci. Instrum. 81, 033107 (2010).
  • [15] A. Kramida et al., NIST Atomic Spectra Database (ver. 5.5.1) [Online] Available: http://physics.nist.gov/asd [2 November 2017] (2017).
  • [16] Y. Liu, S. Morita, X. Huang, T. Oishi, M. Goto and H. Zhong, J. Appl. Phys. 122, 233301 (2017).
  • [17] I. Murakami, H.A. Sakaue, C. Suzuki, D. Kato, M. Goto, N. Tamura, S. Sudo, S. Morita and LHD Experiment Group, Nucl. Fusion 55, 093016 (2015).
  • [18] S.B. Utter, P. Beiersdorfer and E. Träbert, Can. J. Phys. 80, 1503 (2002).
  • [19] T. Pütterich, R. Neu, R. Dux, A.D. Whiteford, M.G. O'Mullane and the ASDEX Upgrade Team, Plasma Phys. Control. Fusion 50, 085016 (2008).
  • [20] T. Pütterich, R. Neu, C. Biedermann, R. Radtke and ASDEX Upgrade Team, J. Phys. B: At. Mol. Opt. Phys. 38, 3071 (2005).
  • [21] Y. Ralchenko, J. Reader, J.M. Pomeroy, J.N. Tan and J.D. Gillaspy, J. Phys. B: At. Mol. Opt. Phys. 40, 3861 (2007).
  • [22] G. Veres, J.S. Bakos and B. Kardon, J. Quant. Spectrosc. Radiat. Transf. 56, 295 (1996).
  • [23] J. Deprince and P. Quinet, Atoms 3, 299 (2015).
  • [24] J. Clementson, T. Lennartsson and P. Beiersdorfer, Atoms 3, 407 (2015).
  • [25] J. Clementson, P. Beiersdorfer, E.W. Magee, H.S. Mclean and R.D. Wood, J. Phys. B: At. Mol. Opt. Phys. 43, 144009 (2010).
  • [26] J. Sugar and V. Kaufman, Phys. Rev. A 12, 994 (1975).
  • [27] J.F. Wyart, V. Kaufman and J. Sugar, Phys. Scr. 23, 1069 (1981).
  • [28] S.S. Churilov, R.R. Kildiyarova and Y.N. Joshi, Can. J. Phys. 74, 145 (1996).
  • [29] R.R. Kildiyarova, S.S. Churilov, Y.N. Joshi and A.N. Ryabtsev, Phys. Scr. 53, 454 (1996).