t kato national institute for fusion science
Download
Skip this Video
Download Presentation
T. Kato National Institute for Fusion Science

Loading in 2 Seconds...

play fullscreen
1 / 50

T. Kato National Institute for Fusion Science - PowerPoint PPT Presentation


  • 162 Views
  • Uploaded on

IAEA 2nd RCM on Atomic Data for Heavy Element Impurities in Fusion Reactors, 26 - 28 September, 2007 EUV spectroscopy from LHD and Atomic Data. T. Kato National Institute for Fusion Science. Introduction. Xe ion spectra and atomic data Fe ion spectra and atomic data

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'T. Kato National Institute for Fusion Science' - carina


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
t kato national institute for fusion science
IAEA 2nd RCM on Atomic Data for Heavy Element Impurities in Fusion Reactors, 26 - 28 September, 2007EUV spectroscopy from LHD and Atomic Data

T. Kato

National Institute for Fusion Science

introduction
Introduction
  • Xe ion spectra and atomic data
  • Fe ion spectra and atomic data
  • Data needs for ITER modelling
xe ion spectra t kato g o sullivan n yamamoto h tanuma et al
Xe ion spectraT.Kato, G. O’Sullivan, N. Yamamoto, H. Tanuma et al
  • We have observed EUV spectra of Xenon ions from the Large Helical Device (LHD) at the National Institute for Fusion Science in Toki in the wavelength range of 10 – 17 nm using a high resolution SOXMOS spectrometer.A small quantity of xenon gas was injected into the Large Helical Device. In some cases, the plasma evolution was stable and a steady discharge was obtained for several seconds, but sometimes the plasma underwent radiation collapse and rapid cooling and in this situation the EUV yield was significantly increased. Investigation of the spectra showed that during the heating phase and in a stable plasma, the emission was dominated by ions with open 4s and 4p subshells, while during radiation collapse, the spectra were dominated by lines from species with open 4d subshells. From a comparison of these spectra with theoretical data from atomic structure calculations and also with charge state specific data generated in Tokyo Metropolitan University it was possible to make tentative assignments of the strongest lines arising from 4d-4f and 4p –4d transitions in Xe XVII and XVIII.
soxmos spectrometer
SOXMOS Spectrometer

(TESPEL)

LHD

plasma

0 deg.

SOXMOS

-1 deg.

24 cm

normal discharge t e
Normal Discharge (Te)

Te(=0) ~ 1000 eV, Te(=0.5) ~ 700 eV

discharge with radiation collapse
Discharge with Radiation Collapse

t = 400 ms

Xe puff

Xe puff

discharge with radiation collapse t e
Discharge with Radiation Collapse (Te)

Te(=0) ~ 500 eV, Te(=0.5) < 200 eV @ t=1.4 s

theory for xe 17
Theory for Xe17+
  • Cowan code

Hatree Fock with Configuration Interaction (HFCI) by G. O’Sullivan (UCD)

  • GRASP2

Multiconfiguration Dirac Fock by D. Kato (NIFS)

  • Cascade model (for charge exchange spectra) by N. Yamamoto (Osaka Univ.)

Grasp code for n = 4, Hullac code for other levels

slide11
Spectral lines during the heating are identified with 4p - 4d transitions of Xe17+ (4d) - Xe25+(4s) ions in 10 - 12 nm

Xe11+,12+

Xe10+

Xe9+

slide13
Spectral lines during the heating are identified from ions with outer 4s or 4p electrons ( Xe23+(4s24p) - Xe25+(4s) ) in 12 - 16nm

t = 400 ms

1. Xe23+

(4s24p)

3. Xe24+

(4s2)

5. Xe23+

7. Xe24+

8. Xe25+

(4s)

11. Xe23+

13. Xe23+

14. Xe24+

1. Xe23+

14. Xe24+

3. Xe24+

7. Xe24+

5. Xe23+

8. Xe25+

11. Xe23+

13. Xe23+

spectra during radiation collapse indicate a recombining plasma
Spectra during radiation collapse indicate a recombining plasma

1. Xe23+

2. Xe18+

24+

3. Xe24+

5. Xe23+

6. Xe10+

7. Xe24+

8. Xe25+

11. Xe23+

12. Xe8+

13. Xe23+

14. Xe24+

  • Many new lines appear in the spectra during radiation collapse.
  • No.2 (131.709A, Xe18+ ?) and No.6 (135.34A, Xe10+?) increase.
  • The continuum emission increases.
  • No.12 is identified as Xe8+. Temperature is low.
quasi continuous background 4p 6 4d m 4p 5 4d m 1 4p 6 4d m 1 4f xe xii xvi m 3 to 7 in 121 155a
Quasi continuous background 4p64dm - 4p54dm+1 + 4p64dm-14f Xe XII - XVI (m = 3 to 7)in 121 - 155A

XVII-XVIII lines are not identified

slide17
Charge Exchange (CX) Spectroscopy of

Xe and Sn ions

by Hajime TANUMA, Hayato OHASHI, Shintaro SUDA

Department of Physics

Tokyo Metropolitan University

xe ion spectra by charge exchange xe q he xe q 1
Xe ion spectra by Charge ExchangeXeq+ + He --> Xe(q-1)+

4p1

Ground state

Configuration

of

Incident ions

4p2

4p3

4p4

4p5

4p6

4p64d

4p64d2

slide20
Dominant capture levels

- prediction with the classical over-barrier model -

It : ionization energy

of the target atom

He : 24.588 eV

Ar : 15.760 eV

Xe : 12.130 eV

slide21
E(4s24p6)=430eV

5p

19

20

5p

5s

16

17

18

13

14

15

5d

11

12

6p

5d

10

n=6

9

8

7p

n=7

4f

n=6

4f

n=5

n=5

4f

4f

4f

n=5

4d

4f

4d

4d

4f

4d

4s24p44d4fnl

4s4p64fnl

4d

4s24p54fnl

4s4p54d2nl

4s24p54dnl

4s4p64dnl

4s24p6nl

4s24p44d2nl

We make a cascade model for CX spectra

Energy Levels Diagram in Radiative-cascade Model

Xe18+ + Xe  Xe17+ (nl) + Xe+  Xe17+ (n’l’) + hv

total energy levels: 8831

Electron transfer

energy band,

dE~1eV

l = 10-12A

l = 12-15A

slide22
Xe17+ Line identification based on 4p64d - 4p54d2 4p64d 2DJ - 4p54d22FJ’2DJ’ (Ground state 4p64d 2D3/2 )Comparison with calculations by GRASP code and Cowan’s code
  • Wavelengths calculated fit well with the known three lines.
  • Broad feature of CX spectrum may be due to cascade transition.
slide23
LHD spectra (yellow) with Cowan (blue) and GRASP (red) code calculations for Xe XVIII for 120 – 150 A. CX spectrum (green) of Xe XVIII
slide24
Cascade Model spectra for charge transfer spectraXe18+ + Xe --> Xe17+ (nl ) --> Xe17+ (n’l’) + hv (by N. Yamamoto)

Strong by cascade

GRASP calc.

Red: w.o. cascade

Blue: with cascade

The wavelengths by GRASP code are shifted by 2.8A.

slide25
Assignments of Rb I like lines in Xe XVIII based on 4p64d-4p54d2 transitions (unless otherwise stated) New (Kato & O’Sullivan)
cx spectra show 4p 5 4d 2 levels are made through charge transfer from 4p 6 inner shell excitation
CX spectra show4p54d2 levelsare made through Charge Transfer from 4p6(Inner shell excitation)
  • Xe 18+ (4p6) + Xe (or He)

---> Xe 17+ (4p54dnl)

or Xe 17+ (4p44d2nl)

---> Xe17+ (4p54d2) + hv (4p - nl)

---> Xe17+ (4p64d) + hv (4p - 4d)

lhd spectrum with xe xvii spectrum cx green cowan code calculations for 120 160 a ga s 1 red
LHD spectrum with Xe XVII spectrum CX (green), Cowan code calculations for 120 – 160 A. gA (s-1) (red)
slide28
Assignments of SrI like lines in Xe XVII 4p64d2 - 4p54d3(Only lines with gA>3x1010 s-1 are included) New

Kato & O’Sullivan (2007)

study of highly ionized xe spectra in jt 60u reversed shear plasmas
規格化小半径

(H. Kubo (JAEA), J. Nucl. Mater., 2007)

In some tokamaks, Xe has been injected to study high-Z impurity behavior or to enhance radiation losses for reduction of heat load to the walls.

Study of highly ionized Xe spectra in JT-60U reversed shear plasmas

Xe spectra (3s-3p & 3p-3d) observed in JT-60U

*The red indicate the lines observed for the first time.

Internal transport barrier

Intensity (arb.)

Xe37+ (1s)2(2s)2(2p)6(3s)2(3p)5

Xez+ density (arb.)

Calculation

Wavelength (nm)

HULLAC and Desclaux’s code were used for the analysis.

r/a

Normalized minor radius

In the reversed shear plasma, we can simply calculate spectral lines from the highly ionized Xe atoms inside the internal transport barrier using a coronal equilibrium model and a collisional radiative model with the electron temperature and density at the plasma center.

軟X線強度分布(arb)

軟X線の測定視野(ch)

summary
Summary
  • EUV Xe ion spectra in 10 ~ 16nm from LHD were measured.
  • Spectra during heating phase are identified to be lines from Xe 23+ (4p, 762.4 eV) to Xe 25+ (4s, 857.0eV). (outer 4s or 4p electrons)
  • They are strong at 25 cm from the center.
  • The spectra from radiation collapse phase are considered to be emitted from Xe8+ (4d10,179.9 eV) to Xe17+ (4d,452.2 eV). (open 4d shell)
  • We have made line identifications for Xe17+ and Xe16+ spectral lines in the wavelength range of 12 - 16 nm.
  • Unidentified lines of highly charged Xe ions are measured in JT60 in the wavelength range of 4 - 16 nm.
  • We will make a theoretical model for Xe ion emissions for LHD and charge exchange spectroscopy by ECR source.
2 fe spectra and atomic data
2. Fe Spectra and Atomic Data
  • Fe is an intrinsic impurity in Laboratory Plasmas
  • Important also in Astrophysics and the Sun
  • We are developing a non-equilibrium model for Fe ion emissions.
  • We studied EUV spectra from Fe XIII ions for plasma diagnostics
  • We evaluate Atomic Data for Fe ions

Ionization, Excitation

euv spectra measured from lhd
FeXIII

FeXII

FeXI

Sum

EUV Spectra measured from LHD

~ FeXIII lines region 196-210A ~

Te=136.6eV, Ne>1013cm-3,

N(FeXI)=1.0, N(FeXII)=3.0, N(FeXIII)=0.4

energy levels for fe xiii lines
(5)

(1)

Ip=361eV

(4)

(3)

(7)

(6)

(2)

3P

3F

1P

1F

3S

3D

1S

5S

1D

3s23p3d

(2,3)

(6)

(1)

3s3p3

(4,7)

(5)

3s23p2

Energy levels for Fe XIII lines

#[email protected]

3p-3d transition (3s23p2-3s23p3d)

(1) 196.525A: 1D2-1F3 (with FeXII)

(2) 200.021A: 3P1-3D2

(3) 201.121A: 3P1-3D1 (with FeXII)

(4) 202.044A: 3P0-3P1

(5) 203.793A+203.826A: 3P2-3D2,3D3

(6) 208.679A: 1S0-1P1

(7) 209.617A: 3P1-3P2

hullac v s aggarwal v s chianti
Hullac -DW

Aggarwal, 2005 –R-matrix

CHIANTI (Landi,1999) -DW

Ne=106cm-3

Ne=1015cm-3

Ne=1010cm-3

Hullac v.s. Aggarwal v.s. CHIANTI

by N. Yamamoto

Te=136eV (=logT[K]=6.2)

hullac aggarwal cij excitation
Hullac / Aggarwal – Cij- excitation

I. Murakami

Aggarwal

Hullac

Hullac

Aggarwal

hullac aggarwal cij excitation37
Hullac / Aggarwal – Cij- excitation

I. Murakami

Aggarwal

Aggarwal

Hullac

Hullac

slide38
3s23p23P0 – 3P1

Fe XIII

3s23p23P0 – 3P2

3s23p23P0 – 1D2

3s23p23P0 – 1S0

Effective collision strength

0 105 3x105 5x105

Te (K)

Tayal S. S., ApJ, 544, 575 (2000)Aggarwal, K. M. & Keenan, F. P., A&A, 429, 1117 (2005)

by I. Skobelev and I. Murakami

slide39
3s23p23P1 – 3s23p3d 3D1 Fe XIII

W

2

Collision strength and effective collision strength

1

G

10 20 30 40

Energy (Ryd)

by I. Skobelev and I. Murakami

Gupta G.P. & Tayal S. S.,ApJ, 506, 464 (1998)Aggarwal, K. M. & Keenan, F. P., A&A, 429, 1117 (2005)

line intensity ratio of fe xiii 2
Line intensity ratio of Fe XIII-2

by N. Yamamoto

by CHIANTI

Atomic Data are important for Plasma Density Diagnostics by Line Ratios

atomic data for ionization of fe ions
Atomic data for Ionization of Fe ions

Experimental data are still not sufficient

by D. Kato

slide43
Fe+15

Ion storage ring measurement

Gregory (1987)

Linkemann

by D. Kato

Linkemann, PRL 74, 4173 (1995)

slide44
Fe+14

Theoretical calculations only

EA is dominant.

Direct cross section is factor three smaller. Younger’s calculations (1983) include the direct cross section only.

by D. Kato

Pindzola et al., Nuclear Fusion special suppl. (1987)

“Recommended data on atomic collision processes involving iron and its ions”

summary for fe ions

Summary for Fe ions

EUV spectral line intensities for Fe XIII are studied

Line ratios with different atomic data are compared

Excitation rate coefficients for Fe XIII are evaluated

Ionization data are surveyed

atomic molecular and surface data needs for iter modelling
Atomic, Molecular and Surface DataNeeds for ITER Modelling

A.S. Kukushkin1, D. Reiter2

1 ITER Organization, Cadarache, France

2 FZ Jülich, Jülich, Germany

Prepared for DCN meeting, October 2007, Vienna

introduction47
Introduction
  • ITER: modelling is the way of extrapolation from present experiments
  • A&M&S data necessary to model the plasma and wall interaction
  • data on surface interactions equally important!
  • Composition of the plasma:
  • fusion reactions  D, T, He
  • mixed materials on PFCs  Be, C, W
  • impurity seeding for core control  Ne, Ar

diagnostics  Li, …

off-normal events  O, Fe, Cu, …

Plasma conditions

Core: fully ionized (but NBI, pellets?), T ~ 0.2 – 20 keV, n ~ 1020 m-3

Edge: a lot of neutrals, T ~ 0.1 – 200 eV, n ~ 1019 – 1021 m-3

This presentation: mostly edge modelling

surface materials w
Surface Materials: W
  • Physical sputtering: rates known (?)
  • No molecules  no chemical erosion (despite carbides?)
  • Ionization, recombination: no full data set; accuracy?
  • Excitation, multi-step ionization?
  • Elastic collisions with D, T ions?
  • – probably unimportant, atomic mass too large
  • Too many charge states, usual multi-fluid approach inefficient
    • “bundling” certain charge states together for transport
    • raw cross-section data + technology for effective rates are needed

Surface properties: hydrogen uptake, interaction with Be, C?

Limited experience in ITER modelling yet (DIVIMP – test particle approximation)

seeded impurities ne ar kr xe
Seeded Impurities: Ne, Ar(, Kr, Xe)
  • Atomic species, no chemistry
  • Ne, Ar very probable candidates for the plasma control;
  • Kr, Xe might cause problems with transmutations, although radiate better
  • Ne: ionisation, recombination data exist for all charge states; accuracy?
    • charge exchange?
    • detailed excitation data? multi-step ionization?
    • elastic collisions with D, T ions – some data exist; accuracy?
  • Ar: the same state as for Ne, probably less reliable?
  • Data for the core conditions equally important
conclusions for iter data needs
Conclusions for ITER data needs
  • Edge modelling is now an essential part of the ITER project
    • design analysis
    • development of the operation strategy
  • It relies strongly on the A&M&S data supplied by the community
    • the results depend on the completeness and accuracy of the data
  • Most important groups of species:
    • Fuel (D, T): data for the edge (A&M) and beam (A, up to 1 MeV). Isotope effects in molecules!
    • Ash (He): data for the edge
    • Wall produced, light (Be, C): data for the edge. Hydrocarbons!
    • Wall produced, heavy (W): data for the edge & core. Bundling!
    • Seeded (Ne, Ar): data for the edge and core
    • Structural materials (Fe, Cu, …): data for the edge and core to analyze severity of possible off-normal events
  • Data on surface interactions equally important for all groups
ad