Transcript Weekly Report
EUV Spectroscopy of Tungsten Observed in SH-Htsc EBIT and related Calculations Yang Yang
Report
@ADAS Workshop 2014, Warsaw, Poland, 30 th Sep. 2014
4/28/2020
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+
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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.
From a talk given by Charles Skinner at the “20 Years of EBIT Spectroscopy” held in Berkeley in 2006
ITER Little spectroscopic data
for tungsten in EUV
W
(20nm-40nm) Only 5 lines from WXII-WXVII
Divertor
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ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014
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
Flat-Field Grating Spectrometer
Vacuum 1.0
× 10 -9 Torr Wavelength Range Resolving Power ( λ/Δ λ) 1-50 nm >1000
SH-Htsc EBIT
E e I e r e 30-4000 eV 10 mA ~120 μm Vacuum <1.0e
-9 Torr Magnetic field 0-0.25 T Z. Shi,
et al.
, Rev. Sci. Instrum. 85, 063110 (2014) J. Xiao,
et al.
, Proceedings of IPAC2013 MOPFI066 (2013) 4
ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014
3. Experimental Results
- Calibration first
Operation Parameters
E e I e Gas Injection Injection Pressure Vacumm 200-400 eV 8.1 mA W(CO) 6 6.0
× 10 -8 < 1.0
× 10 -9 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 5
ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014
3. Experimental Results
The ionization potential of W 10+ to W 15+ *
* A.E. Kramida and T. Shirai, Atomic Data and Nuclear Data Tables 95, 305C474 (2009)
Spectra taken at beam energies from 200 to 410 eV
Most spectral lines were seen in the region between 170-260 Å 6
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)
* M. F. Gu, Canadian Journal of Physics 86, 675 (2008)
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4. Calculation methods and results
Configurations used in the RCI model of W 11+ ~ W 15+
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4. Calculation methods and results
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)
The synthetic spectra of W 10+ to W 15+ with CR model
Most distinct lines lay on wavelengths between 160 Å ~ 270Å, that is coincident with experimental results 9
ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014
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
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5. Comparisons
between experiments and calculations
• Slight shift in wavelength • packages of peaks are wider.
•Δn = 0 160 190Å 5d → 5p 210 260Å 5p → 5s
Experimental spectra of W 10+ to W 15+ The synthetic spectra of W 10+ to W 15+ with CR model
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5. Comparisons
between experiments and calculations
Comparison with LHD spectra
Quasi-continuum spectra around 30nm observed in LHD Many Thanks to Suzuki san.
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6. Identification of Ground state of W
13+
4f 13 5s 2 resonance doublet lines 4f 14 5s 1/2
spectrum was recorded on Berlin EBIT at beam energy of 300eV
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)
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6. Identification of Ground state of W
13+
1/2
Experimental spectra at 320eV the level structure of W 13+ from RCI method
4f 13 5s 2
Visible transitions: Z. Z. Zhao, submitted (2014)
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Synthetic spectra at 310eV
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.
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ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014
Thank you for your attention !
Members in Shanghai EBIT Laboratory ADAS Workshop 2014 - Warsaw, Poland 30 th Sep. 2014
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