1. 1/15/2015 Report YY EUV Spectroscopy of Tungsten Observed in SH-Htsc EBIT and related Calculations Yang Yang Shanghai EBIT Laboratory Institute of Modern Physics, Fudan University, Shanghai, China @ADAS Workshop 2014, Warsaw, Poland, 30 th Sep. 2014

2. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 Outline: 1.Much Attentions to Tungsten Spectroscopy 2.Devices well fit the measurements of EVU Spectroscopy of Tungsten 3.Experimental Results (Preliminary) 4.Calculation methods and results 5.Comparisons between experiments and calculations 6.Identification of Ground state of W 13+ 2

3. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 1. Much Attentions to Tungsten Spectroscopy A strong candidate for plasma facing material for future fusion devices, such as ITER High radiation power which may degrade the plasma performance Great need of tungsten spectroscopy for ITER diagnostics was pointed out by Skinner in 2006. Little spectroscopic dataLittle spectroscopic data for tungsten in EUV 3 ITER W From a talk given by Charles Skinner at the “20 Years of EBIT Spectroscopy” held in Berkeley in 2006Divertor (20nm-40nm) Only 5 lines from WXII-WXVII

4. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 Devices 2. Devices well fit the measurements of EVU Spectroscopy of Tungsten Shanghai High Temperature Super-Conductor EBIT(SH-Htsc EBIT) High resolution extreme ultraviolet (EUV) and soft x-ray spectrometer 4 SH-Htsc EBIT EeEe 30-4000 eV IeIe 10 mA rere ~120 μm Vacuum<1.0e -9 Torr Magnetic field 0-0.25 T Flat-Field Grating Spectrometer Vacuum1.0×10 -9 Torr Wavelength Range 1-50 nm Resolving Power (λ/Δ λ) >1000 Z. Shi, et al., Rev. Sci. Instrum. 85, 063110 (2014) J. Xiao, et al., Proceedings of IPAC2013 MOPFI066 (2013)

5. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 5 Fig. Spectrum for Calibration taken at a beam energy of 120 eV and a current of 8.1mA. Oxygen and Nitrogen are from the residual gas in the SH-Htsc EBIT 3. Experimental Results Operation Parameters EeEe 200-400 eV IeIe 8.1 mA Gas InjectionW(CO) 6 Injection Pressure 6.0×10 -8 Vacumm< 1.0×10 -9 - Calibration first

6. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 6 Spectra taken at beam energies from 200 to 410 eV The ionization potential of W 10+ to W 15+ * * A.E. Kramida and T. Shirai, Atomic Data and Nuclear Data Tables 95, 305C474 (2009) 3. Experimental Results Most spectral lines were seen in the region between 170-260 Å

7. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 4. Calculation methods and results Flexible Atomic Code(FAC)* - Relativistic Configuration-Interaction(RCI) - Collisional-Radiative Modeling (CRM) 7 * M. F. Gu, Canadian Journal of Physics 86, 675 (2008)

8. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 8 4. Calculation methods and results Configurations used in the RCI model of W 11+ ~ W 15+

9. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 9 4. Calculation methods and results The synthetic spectra of W 10+ to W 15+ with CR model Results after CRM calculation and line broading: E e =230,270,310,350,390eV N e =5.0×10 -10 cm -3 Resolving Power = 850 (for simulation) Most distinct lines lay on wavelengths between 160Å ~ 270Å, that is coincident with experimental results

10. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 10 4. Calculation methods and results Summary about the transitions contributing to the spectra The synthetic spectra of W 10+ to W 15+ with CR model

11. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 5. Comparisons between experiments and calculations 11 The synthetic spectra of W 10+ to W 15+ with CR modelExperimental spectra of W 10+ to W 15+ Slight shift in wavelength packages of peaks are wider. Δn = 0 160-190Å 5d → 5p 210-260Å 5p → 5s

12. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 12 5. Comparisons between experiments and calculations Quasi-continuum spectra around 30nm observed in LHD Many Thanks to Suzuki san. Comparison with LHD spectra

13. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 13 6. Identification of Ground state of W 13+ spectrum was recorded on Berlin EBIT at beam energy of 300eV 4f 13 5s 2 4f 14 5s resonance doublet lines no yes C. L and E. D. Alkalilike, Physical Review Letters 45(26), 2099 (1980) T. C. E and R. V., Physical review. A, General physics 28(2), 1186C1188 (1983) A. K. a and T. Shirai, Atomic Data and Nuclear Data Tables 95, 305C474 (2009) R. Hutton, Y. Zou, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 205, 114 (2003) 1/2

14. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 14 6. Identification of Ground state of W 13+ the level structure of W 13+ from RCI method Experimental spectra at 320eV Synthetic spectra at 310eV 4f 13 5s 2 Visible transitions: Z. Z. Zhao, submitted (2014) 1/2

15. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 Summary EUV Spectra of W 11+ ~ W 15+ ions have been studied both experimentally and theoretically. Preliminary comparison between them have been done. Identification of the ground-state configuration of W 13+ has been done, which shows 4f 13 5s 2 should be the lowest configuration. 15

16. ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014 16 Thank you for your attention ! Members in Shanghai EBIT Laboratory