Introduction to AMODS
The 19th IAEA
1
DCN Meeting
2007. 10. 4.
IAEA Headquarter, Vienna
Yongjoo RHEE
Laboratory for Quantum Optics
Korea Atomic Energy Research Institute (KAERI)
yjrhee@kaeri.re.kr
http://amods.kaeri.re.kr
2
CONTENTS
1. Introduction to Laboratory for Quantum Optics, KAERI
2. High resolution atomic spectroscopy
- auto-ionization level, hyperfine splitting, isotope shift
- spectroscopy apparatus
- theoretical calculation (Isotope shift of Sm)
3. Atomic processes in a fusion plasma (NIST)
- electron impact ionization cross sections of W/Mo
Th
Exp
Th
4. Emission spectra of highly charged ions
- calculation of Xe10+ spectra (NIFS)
- spectra of highly charged W ions
5. Nuclear fusion
- small scale laser fusion
- neutron yield
Exp
6. AMODS database
Th
7. Summary
1
Based on the “Atomic Physics”, atomic spectroscopy and nuclear
fusion research are pursued at Lab. for Quantum Optics, KAERI.
Density matrix
STIRAP
isotope shift
hyperfine structure
autoionization
Atomic Spectroscopy
3
Laser-induced
plasma
Atomic Physics
Fusion Research (MFE, IFE)
- Korea (KAERI, NFRC, KAIST, GIST)
- Japan (NIFS, ILE)
- China (SIOM, CAEP, IOP)
Laser Propagation
Population Dynamics
AMODS
Relativistic structure calculation
Electron impact ionization
Radiative transition of HCI
2
High resolution laser spectroscopy facility has been established
to measure the atomic parameters such as IS, HFS, AI levels.
Nd:YAG Laser
Freq stab.
Dye Laser 1
Dye Laser 2
Wavemeter
SLM
SLM
Dye Laser 3
Lock-in
Amplifier
MCP
TOF
Pulsed 3-step MPI lasers
PD1
DPSS Laser
PD2
Short Pulse Laser
Heat Pipe Oven
SH Generator
CW narrow-band laser system
Digital
Oscilloscope
Atomizer
Broad-band short pulse lasers
CW Diode Laser
Multichannel
Analyzer
Hollow Cathode Lamp
Powermeter
Atomic spectroscopy for rare earth elements (57-71)
La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu
PD3
PD4
Boxcar
Control
Computer
Periodic Table of Elements
4
Electronic energy level shifts are due to the interaction of electron
with nuclei (proton and neutron) as well as other electrons.
 Isotope Shifts : Shifts of
electronic energy levels due to
different number of neutrons
in isotopes even with the same
number of protons and electrons
 Hyperfine structure : splitting of
electronic energy level due to
proton spin – electron orbital,
proton spin – electron spin
interaction.
 Autoionixation level:
bound state above the ionization
threshhold energy
5
Energy level structure should be known precisely for multi-step
ionization processes.
Multi-step excitation/ionization of Yb (Z=70)
G = 14 cm-1
ionization potential.
170 171
168
582.782nm
s = 7.8 x 10-15 cm2
t=1.2 ms
171
J=3
1.5 GHz
J=2
4.0 GHz
4.3 GHz
581.067nm
d=4.3 x 10-31 C m
t =840 ns
J=1
170
555.648nm
171
168
d=2.7 x 10-30 C m
ground level
173
J=0
1.3 GHz
1.4 GHz
0.15 GHz
6
Detection of fluorescence characteristics can give an information
on the ionization efficiency.
Nd:YAG laser
w3
Dye
laser 1
Dye
laser 2
Dye
laser 3
Gd
ionizing laser
w2
fluorescence
w1
Wavemeter
Monochromator
Computer
Lens
PMT
Lens
Deflection
plate
Drift tube
Oscilloscope
Optical fiber
Acceleration
grids
Gd atomic
beam
Micro channel
plate
Time-of-flight
mass spectrometer
Photoionization efficiency from the second excitation level to the continuum state
can be estimated by observing the decrease of fluorescence signal from the
second level.
7
8
Isotope shift can be analyzed by “King” plot method to investigate
the effect due to mass and volume separately
Doppler-free SAS spectrum
Atomic Transition Lines
5d
6s2
4f6 6s 6p
1.4x10 -3
4
Intensity(arb.units)
4f5
7F
399.002 nm
7F
1
672.588 nm
4f6 6s2
7F
5
7F
0
1.2x10 -3
(4f66s2 7F0  4f6 6s 6p 7F1)
152 Sm
154 Sm
1214.8 MHz
15 MHz
1.0x10 -3
147 Sm
148 Sm
8.0x10 -4
144 Sm
150 Sm
6.0x10 -4
2265.6 MHz 1608.8 MHz
2739.5 MHz
4.0x10 -4
144 Sm
Modified isotope shifts of transition lines
(MHz)
2.0x10 -4
0.0
King plot analysis
0
2000
150-148
148-144
154-152
500
0
-500
154-152
-1000
150-148
-1500
148-144
-2000 152-150
(4f66s2 7F5  4f5 5d6s2 7F4)
3.5x10 -4
Intensity (Arb. Unit)
1000
-2000
-1800
-1600
-1400
-1200
Modified isotope shifts of 598.97nm transition (Reference)
(MHz)
8
10
152 Sm
3.0x10 -4
801.6 154 Sm
MHz
2.5x10 -4
2.0x10 -4
1.5x10 -4
1799.6 MHz
1.0x10 -4
147 Sm
5.0x10 -5
-2200
4
6
Relative Frequency ( GHz)
399.002 nm
672.588 nm
1500 152-150
-2500
-2400
2
148 Sm
1158.3 MHz
149 Sm
150 Sm 1825.9 MHz
144 Sm
0.0
0
1
2
3
4
5
Frequency Detuning (GHz)
6
7
Isotope shifts of Sm (Z=62) have been measured for various levels
and compared with the theoretical calculation using MCDF
4f5 5d 6s2 7F4
28180.95 cm-1
4f5 5d 6s2 7F3
19501.27 cm-1
18948.78 cm-1
18475.28 cm-1
18075.67 cm-1
17830.80 cm-1
17810.85 cm-1
17769.71 cm-1
4f5 5d 6s2 7H3
17190.20 cm-1
4f6 6s2 7FJ
399.00 nm c
580.28 nm b
599.51 nm b
565.99 nm b
562.18 nm b
5
4
3
2
1
0
587.42 nm b
14863.85 cm-1
570.68 nm b
9F
1
562.60 nm b
4f6 6s 6p
7F
1
7H
2
7F
3
7F
0
7F
1
7F
2
591.64 nm b
5d 6s2
5d 6s2
6s 6p
6s 6p
6s 6p
6s 6p
672.59 nm a
4f5
4f5
4f6
4f6
4f6
4f6
3125.46 cm-1
2273.09 cm-1
1489.55 cm-1
811.92 cm-1
292.58 cm-1
0 cm-1
9
Comparison of calculated isotope shifts of neutral Sm atom agrees
well with the experimental data.
Transition line
(nm)
10
MCDF values (Ei/Eref)
Classification
Experimental
values (Ei/Eref)
single config.
multiple config.
672.588
4f66s2 7F0  4f66s6p 7F1
0.98
0.97
0.97
591.64
4f66s2 7F1  4f66s6p 7F2
1.00
1.02
1.02
562.60
4f66s2 7F0  4f66s6p 7F1
0.19
1.02
1.02
570.68
4f66s2 7F1  4f66s6p 7F0
0.76
1.02
1.02
587.42
4f66s2 7F2  4f66s6p 7F3
1.00
1.03
1.03
562.18
4f66s2 7F1  4f55d6s2 7H2
-1.51
-2.18
-1.35
565.99
4f66s2 7F2  4f55d6s2 7F1
-1.02
-2.19
-1.03
599.51
4f66s2 7F4  4f55d6s2 7H3
-1.34
-2.17
-1.32
580.28
4f66s2 7F4  4f55d6s2 7F3
-1.03
-2.18
-1.03
399.002
4f66s2 7F5  4f55d6s2 7F4
-0.98
-2.22
-1.02
Relativistic MCDF code can calculate atomic structure and
transitions.
11
Multi Configuration Dirac-Fock (MCDF) code :
Jean-Paul Desclaux (Grenoble, France)
Paul Indelicato (University of Paris, France)
Yong-Ki Kim (NIST, USA)
- ralativistic wave functions
- electric and magnetic multipole transition
- plane wave Born cross section
- angular coefficients, etc
Dirac-Fock Equation
 d κA εAA
 dr + r - c

VA (r)

 - c
Screened Coulomb
charge term
Radial function X
r
VA (r)

-2c 
εA,B
 P (r) 
c
 A
=
 
d κA εAA   QA (r)  B =A c
- dr r
c 
Exchange term
 QB (r)   XQA (r) 


 +  -X
-P
(r)
 B
  PA (r) 
Lagrange multipliers
http://amods.kaeri.re.kr/mcdf/MCDF.html
PC version – downloadable from MCDF site
Workstation version (2000)
3
Atomic processes in a fusion plasma are very complicated and can
have serious effects on the plasma status.
Plasma (keV)
2nd
electron,
ion,
excited atom
12
electron
plasma-wall
interaction
Mo, W, V
generation
of elctron
photon
impurity
secondary electron
secondary
electron
photon emission
plasma particle
Plasma
p, e, Be, Li, C, Ni, etc
진단용 중원소 (Ar, Xe, etc)
electron collision
with plasma
decrease of plasma
temperature
energy loss of
plasma
Electron impact ionization cross sections are essential data for
fusion plasma and can be calculated by using MCDF code.
Direct Ionization
Excitation Autoionization
Continuum
Continuum
Bound state
BEB (Binary Encounter Bethe) model
Bethe
s orb
Mott
Excited state :
autoionization or
photoemission
First ionization
limit
Ionization
energy
Electron
13
interference
4 a02 N ( R / B)2  ln t  1 
1 ln t 
=
1  2   1  

t  (u  1) / m  2  t 
t 1  t 
N : Orbital Occupation Number B : Orbital Binding Energy
U : Orbital Kinetic Energy
R : Rydberg Energy
T : Incident Electron Energy
t = T/B u = U/B
a0 : Bohr Radius
Electron
Bound state 2
Bound state 1
T
s BE =
s PWB
T BE
T
sE =
s CB
T E
E: excitation energy
B: bound energy
PWB: plane wave Born Approximation
for neutral atom
CB: Coulomb Born approximation
for singly charged ion
Electron impact ionization cross sections of neutral atoms are very
difficult to obtain experimentally.
Energy levels of W
(Z=74, m=meta stable state, g=ground state)
Atom
W
W+
Configuration
LS term
Level [eV]
Ionization
energy [eV]
5d4 6s2
5D
0
(g)
0
7.864
5d5 6s
7S
3
(m)
0.3659
5d4 6s2
3P
1
(m)
1.6499
5d4 6s
6D
1/2
(g)
0
5d5
6S
5/2
(m)
0.9200
5d3 6s2
4F
(m)
1.0801
5/2
* So far W, Mo, V, Li, Be, C, etc have been studied
16.35
14
Electron impact ionization cross sections of singly charged W ion
have been calculated and compared with experiments
e-impact ionization of W+ ion
15
Electron impact ionization cross sections of neutal W atom
have been calculated and compared with other calculation
e-impact ionization of neutral W
16
Online calculation of direct ionization cross section bases on BEB
is possible in AMODS for W and Mo.
17
4
Emission spectra of highly charged ions are required in EUV
source development and fusion plasma diagnostics.
EUV spectrum from Xe10+:
► development of projection lithography at EUV wavelengths of 13.5 nm
- highly reflective multilayer mirror (Mo/Si) ~ 70%
- spectra from Xe10+ :
4d8  4d74f + 4d54d9 : 11.1 ~ 11.3 nm
4d8  4d75p : 13.0 ~ 14.0 nm
► plasma diagnostics in the magnetic fusion devices
- electron temperature, gas temperature
- plasma densities, species concentrations
spatially resolved data : to map plasam density
temporally resolved data : to study dynamics of pulsed plasma
10.7 m GIM
1200 lpm
Spectrum of Xe excited in low inductance vacuum spark (NIST, 2004)
18
MCDF code has been applied to the calculation of transition
probabilities of Xe10+ and/or W33+ to W37+.
4p64d9 +
4p64d75p1 +
4p64d74f1
To see the effects of
configuration interaction
4d8 (J=3,4)  4d75p
ΔJ=0, ±1
4p64d8
(HULLAC code – multiconfiguration)
T. Kato, EUVL2004
19
Emission spectra of highly charged W ions are measured at the
EBIT and compared with calculation (HULLAC).
4p64dn – [4p5 4dn+1 + 4p64dn-14f]
Series of EUV spectra of W ions (25+
to 36+) measured at Berlin EBIT
HULLAC code, C. Biedermann,
Physica Scripta, 2001
20
Spectra of highly charged W ions have been measured by many
groups since W are thought to be a candidate for the PFW material
ASDEX upgrade, R. Neu, J.Phys.B, At. Mol. Opt. Phys. 1997
21
22
Spectra of highly charged W ions in the soft X-ray range are obtained
in the ASDEX and EBIT facilities and compared with calculations.
RELAC code, R. Neu et al
J.Phys.B, At. Mol. Opt. Phys. 1997
Energy levels of Mo ions are relatively well known whereas those
of highly charged W ions are not.
W37+
W36+
W35+
W34+
W33+
← Mo VI
← Mo V
← Mo IV
← Mo III
← Mo II
23
Electronic configurations of highly charged W ions are assumed
to be the same as Mo ions.
Mo ion
Ground
configuration
Term symbol
Total angular
momentum
Mo1+
[Kr] 4d5
6S
5/2
0
W33+
Mo2+
[Kr] 4d4
5D
0
0
W34+
1
0 .030009
2
0 .082851
3
0 .151752
4
0 .232137
Mo3+
Mo4+
Mo5+
[Kr] 4d3
[Kr] 4d2
[Kr] 4d1
4F
3F
2D
Energy [eV]
3/2
0
5/2
0 .096462
7/2
0 .218183
9/2
0 .355163
2
0
3
0 .195631
4
0 .416257
3/2
0
5/2
0 .320410
REMARK
(W ions)
W35+
W36+
W37+
24
Spectra of highly charged W ions ranging from W33+ to W37+ have
been obtained by the calculation using MCDF code
W34+ (n=4) : 4p64dn  [ 4p5 4dn+1 + 4p64dn-14f ]
W33+
W34+
W35+
W36+
W37+
25
5
Nuclear fusion can be induced by a ultra short pulse intense
laser irradiated on a D2 cluster or deuterated polymers.
T. Ditmire. LLNL, Nature, 1999
d + d  He3 + n
~104 neutron/pulse
- Point source
- Very short duration(<ns)
- Nearly monochromatic (~2.45 MeV)
26
Ultra short pulse Ti:Sapphire laser is used on a dPS (deuterated
polystyrene) thin film to generate 5X105 neutrons/shot
To
monitor
CCD camera
to monitor
focal spot in
the target
He3
detector
on top of
chamber
cover
DPS target
Detectors:
He3
CR39
Faraday cup
To
monitor
CR39 in
Pb foil
To oscilloscope
focusing lens
for CCD
360 mm
CR39 in
Pb foil
60 mm
Deuterated
polystylene
target
Goldcoated
mirror
CCD camera to
monitor front
surface of target
Faraday cup
320 mm
178 mm
f/3 45o
off-axis
parabolic
mirror
diaphragm
Laser beam :
800nm, 400mJ, 30fs,
10 Hz, p-polarized
CR39 in Pb foil
(out of chamber)
Top cover of
chamber
is made of
acryl plate
Laser facility
in APRI/GIST
27
28
Ultra short pulse Ti;Sapphire laser is applied to the D2 clusters
to generate 1,000 neutrons/shot
Compressed laser beam
of 30fs pulse width
F/12 (f=75cm) lens
on a translation
stage
 D2 gas is fed through a solenoid
nozzle valve with 0.5 mm orifice.
 Backing pressure is measured at the
regulator of D2 gas
 Nozzle assembly is cooled down by
liquid nitrogen.
 Opening time of nozzle is 2 ms
25 cm
LN cooled
D2 gas jet
3cm
CR-39
in Pb
foil)
D=37 cm
FC
end position
of translator
I
variable focal point
12.8 mm (variable position)
278646 (encoder reading)
plastic
scintillator
(0.79 nsV/neutron)
PE50BB
calorimeter
Neutrons are generated from the nuclear fusion reactions in the
deuterated polystyrene and deuterium clusters.
Deuterated polystyrene target after irradition
(thickness: 0.04 mm, bored hole : 0.02 mm) (KAERI, 2005)
Scattered light of Ti:Sapphire laser from deuterium
clusters (KAERI, 2006)
29
Pits made on the CR-39 detector by
recoiled ions hit by neutrons (KAERI, 2005)
Neutron signal (scintillator), laser signal
(PD), charged particle signal (Faraday
1D PIC simulation of laser-plasma interaction gives an information
about the ion density profile as a function of time
2λ (1.6 μm)
LPIC++ code
λ= 800 nm
T = 1/ν= λ/c
= 800 [nm]/ 3X108 [m/sec]
= 2.7 [fs]
τ= 10 T = 27 fs (pulse width)
Iλ2 = a02 X 1.37 X 1018 Wum2/cm2
a0 = 2.0 – 4.0, p-polarization
0
0.5
1.0
1.5
2.0
1000 cells/wavelength
Simulation time = 200 T = 540 fs
Travel length = 540X10-15 [sec]X3X108[m/sec]
= 1.6 X10-4 [m] = 160μm
Ion density profile
 Velocity of shock front = 5 X 106 m/s
30
6
31
AMODS database
32
Structure & Data Sources of AMODS
Collisions and Reactions
Atomic Structure & Transitions
MPI
PATH
IAEA,ORNL
NIFS
Michigan
NIST, CUP
CDS
Fusion Simulation
KAERI
NIST
Strathclyde
KAERI
KAERI
Most data retrievals are controlled by SCRIPTS (PERL, k-shell)
NIST
NIST
33
Atomic Spectral Lines - I
34
Atomic Spectral Lines - II
35
Population dynamics of level atom
36
Electron impact excitation/ionization
37
Electron Impact Differential Cross Sections
Implemented in NIFS under CUP
38
KAERI – NIFS collaboration
39
Dielectronic Satellite Lines - NIFS
40
Mirror Site of NIST ASD
41
Isotope Data
SUMMARY
Unique atomic spectroscopy facility in KOREA has been established.
- Experiments and theoretical studies are possible
- Korean representative AMO DB (IAEA DCN)
structural database
collisional database
Spectroscopic studies for fusion research have been pursued.
- W, Mo, Be, C, etc
- ITER, KSTAR
- International collaboration (NIFS, NIST, RAL, …)
Ultra-fast radiation technology is under development
- First demonstration laser fusion in Korea
- Industrial applications of fast neutron
Computer codes for fusion plasmas are under development.
 laser fusion
 magnetic fusion
42