低電離タングステンイオンの電子捕獲断面積測定Cross Sections for

Electron Capture Collision of W Ions

京都大学工学研究科原子核工学専攻京都大学工学研究科原子核工学専攻今井 誠，入来 仁隆

Makoto IMAI, Yoshitaka IRIKIDepartment of Nuclear Engineering, Kyoto University

原子分子データ応用フォーラムセミナー, NIFS, Feb 19, 2010

Status for charge transfer collision cross section of ionsStatus for charge transfer collision cross section of ions

H He ◎H, He ◎

Li, Be, ・ ・ ・, Ne ○

Na, ・ ・ ・, Ar △

以降 Fe, Cu, U等ごく一部

Status for charge transfer collision cross sections for WStatus for charge transfer collision cross sections for W

Measured cross section for single electron captureby Meyer et al at 8 5 11 MeV (46 60 keV/u) in PRA19 515 (1979)by Meyer et al. at 8.5, 11 MeV (46, 60 keV/u) in PRA19, 515 (1979).

Wq+ + H, H2, Ar (q = 6−15)

( )( )

2

16 1.3

16 1 1

1.6 10 2H

2

cmqσ −= ×

1.E‐14

( )16 1.12.4 10 2Ar cmqσ −= ×

1 E 151.E‐15

2 4 6 8 10 12 14

Status for charge transfer collision cross sections for WStatus for charge transfer collision cross sections for WMeasured cross section for single electron captureby Meyer et al. at 8.5, 11 MeV (46, 60 keV/u ) in PRA19, 515 (1979).

Wq+ + H, H2, Ar (q = 6−15)

Production (measurements) of electron capture cross sectionsProduction (measurements) of electron capture cross sections for some fusion-related processes in Kyoto University

W+ W2+ + He Ne Ar Kr H N CH C HW , W2 + He, Ne, Ar, Kr, H2, N2, CH4, C2H6

Theoretical study of single ionization of W ion by Ar by V P Shevelko (P N Lebedev Physical Institute Russia)by V. P. Shevelko (P. N. Lebedev Physical Institute, Russia)

W+ + Ar

Theoretical study of electron capture of W ion by R. J. Buenker (Bergische Universität Wuppertal, Germany)

W+ + H, He, H2

Production of Absolute Cross Sections forFusion Related Electron Capture ProcessesFusion Related Electron Capture Processes

Energy = (0.5) 5 - 32 keVTill 1994C1,2,3+ + H2 , CO2 , CH4 , C2H6 , C3H82 , 2 , 4 , 2 6 , 3 8

1995 − 1997Cr1,2+ + He, Ne, Ar, Kr, H2 , CO, CO2 , CH4 , C2H6 , C3H8Be1,2+ + He Ne Ar Kr H CO CO CH C H C H Be will be used asBe1,2+ + He, Ne, Ar, Kr, H2 , CO, CO2 , CH4 , C2H6 , C3H8

1998 − 2000Ni1,2+ + He, Ne, Ar, Kr, H2, CO, CO2 , N2 , CH4 , C2H6 , C3H8

Be will be used asthe First Wall Materialin the ITER!

, , , , 2, , 2 , 2 , 4 , 2 6 , 3 8

2001 − 2004Fe+ + He, Ne, Ar, Kr, H2 , CO, CO2 , N2 , CH4 , C2H6 , C3H8B 1 2+ + H N A K H CO COBe1,2+ + He, Ne, Ar, Kr, H2 , CO, CO2B1,2+ + He, Ne, Ar, Kr, H2 , CO, CO2

2005 − present W will be used for2005 presentW+, W2+ + He, Ne, Ar, Kr, H2 , N2 , CH4 , C2H6 DIVERTOR Buffle and

Dome in the ITER!

IAEA Coordinated Research Project (CRP) on “Atomic Data for HeavyIAEA Coordinated Research Project (CRP) on Atomic Data for Heavy Element Impurities” (2005 – 2009) requires data for elements with atomic mass ≥ 13; (Ar, Kr, Xe), Si, Cl, Cr, Fe, Ni, Cu, Mo and W!

10-15 HeNeAr

10-16m

2 )ArKr

10-18

10-17

c t i

o n

(c

m

(a) Be+, 2+ (b) B+, 2+

H2

CH4

C2H6o s

s S

e c

10-15

C3H8

COCO2

C r

10-17

10-16

σ10

10-18

10-17 σ10

σ21

σ20theories(a') Be+, 2+ (b') B+, 2+

Si l d d bl l t t ti d f B d B i

1.0E n e r g y (keV/u)

1.00.3 0.35.0 5.0

Single and double electron capture cross sections σ10, σ21 and σ20 for Be and B ions.

J. Plasma Fusion Res. SERIES Vol.7, pp.323-326.

10-15 σ10HeAr

σ21σ20

10-17

10-16Layton et al.

m2 )

Krσ20

10-18

c t i

o n

(cm

(a) Fe+ (b1) Ni+ (b2) Ni2+

10-19

r o s

s S

e c

10-15H2

CH4

C2H6

C r

10-17

10-16 C3H8

COCO2

N2

10-19

10-18

(a') Fe+ (b1') Ni+ (b2') Ni2+

Si l d d bl l i d f F d Ni i

E n e r g y (eV/u)

1010 10050 50100 1001000

Single and double electron capture cross sections σ10, σ21 and σ20 for Fe and Ni ions.

J. Plasma Fusion Res. SERIES Vol.7, pp. 323-326.

The Experimental Apparatusp pp

Neutral Particle Rejector

Pump Beam0.9 MeV (20 keV/u) CO2

＋

Base PressureBase Pressure< 3×10−6 Pa

Einzel LensAccelerating Electrodes

Neutral Particle Rejector

Deflector

< 4×10−5 PaEinzel Lens

Collision CellSignal 1

Wien FilterIon Source Chamber

W WireMCP

Biased Resistive Anode

Accel. HV< 16 KV

Collision Chamber

Signal2

チャンネル径 12μm開口率 60%

MCP

Projectile W Ion Selection

1E+4

7.5 keV W+ Extraction

j

1E+4

W+WO+

1E+3

eld WO2

+

1E+2

Ion Y

ie

W2+

W2+

1E+1

1E+0

0 256 512 768 1024

Wien Filter Electric Field mq∝

The Experimental Apparatusp pp

Neutral Particle Rejector

Pump Beam0.9 MeV (20 keV/u) CO2

＋

Base PressureBase Pressure< 3×10−6 Pa

Einzel LensAccelerating Electrodes

Neutral Particle Rejector

Deflector

< 4×10−5 PaEinzel Lens

Collision CellSignal 1

Wien FilterIon Source Chamber

W WireMCP

Biased Resistive Anode

Accel. HV< 16 KV

Collision Chamber

Signal2

チャンネル径 12μm開口率 60%

MCP

How to Derive Cross Sections

Rate equation for Wi+ intensity ( ) ( ) ( ) ,ij ji i ij

dFF F

dπ

π σ π σπ

⎡ ⎤= −⎣ ⎦∑( ) 1,

j j jj i

ii

d

F

π

π≠⎣ ⎦

=

∑

∑where

Relative Intensity of Wi+ ion2

( ) :iF πTarget Thickness (= Density× Length in /cm2)Charge Transfer Cross Section (cm2) Wj+ → Wi+

::ji

πσ

Under the Single Collision Condition, this simultaneous equation reduces to 20 πσπσ ==

IIreduces to where

Intensity of W2+ W+ and W0 respectively

,, 12012

10012

πσπσ =++

=++ IIIIII

III Intensity of W2 , W and W0, respectively.:,, 012 III

Data ProcessinggBench mark for 7.5 keV H+ + H2 collision

I

Growth Curve for 5 keV W+

,10012

0 πσ=++ III

I

Single Electron Capture Cross Sections for W+ Ionson Gas Targets at 10 and 5 keV (54 and 27 eV/u)on Gas Targets at 10 and 5 keV (54 and 27 eV/u)

10 keV W+ Single Electron Capture 5 keV W+ Single Electron Capture

C2H6 C2H6

10-16

n (c

m2 )

ArKr

CH4

CH4

10-17s Se

ctio

n Kr

N2IP -4.99

10

Cro

ss

Ne

H2 IP -17.3

IP -9.18

10-18

10 15 20 25

He Ne(7.5 keV)

10 15 20 25

IP

10 15 20 25Target Ionization Potential (eV)

10 15 20 25Target Ionization Potential (eV)

Single Electron Capture Cross Sections for W2+ Ionson Gas Targets at 15 keV (82 eV/u)on Gas Targets at 15 keV (82 eV/u)

15 keV W2+ Single Electron Capture

CH4

C2H6

10-15n

(cm

2 ) Kr4

10-16s Se

ctio

n

10

Cro

ss He

10-17

10 15 20 2510 15 20 25Target Ionization Potential (eV)