Petersburg Nuclear Physics Institute
DOUBLE POLARIZED DD-FUSION
P. Kravtsov, N. Chernov, K. Grigoryev, I. Ivanov, E. Komarov,
L. Kotchenda, M. Mikirtychyants, S. Sherman, S. Terekhin
V. Trofimov, A. Vasilyev, M. Vznuzdaev
Petersburg Nuclear Physics Institute, Gatchina, Russia
R. Engels, L. Kroell, F. Rathmann, H. Stroeher
IKP, Forschungszentrum Juelich, Germany
H. Paetz Gen. Schieck
IKP, University of Cologne, Germany
M. Marusina, S. Kiselev
University ITMO, St.Petersburg, Russia
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P. Kravtsov
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Participating Institutions
Petersburg Nuclear Physics Institute, Russia
Forschungszentrum Jülich, Germany
Cologne University, Germany
KVI, Gronningen, Netherlands
University ITMO, St.Petersburg, Russia
Ferrara University, Italy (?)
Financial support:
ISTC project #3881
Deutsche Forschungsgemeinschaft
Ministry of Science and Education
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Double polarized dd-fusion
The main 4-nucleon fusion reaction – good testing ground for
microscopic calculations
t+p
d + d
3He
+n
• Systematic measurements of the spin-correlation coefficients
• Cross section increase
[R.M. Kulsrud et al., Phys. Rev. Lett. 49, 1248 (1982)]
3He+d → 4He+p : Factor ~1.5 at 430 keV
[Ch. Leemann et al., Annals of Phys. 66, 810 (1971)]
• Neutrons suppression
Quintet suppression factor
[H. Paetz gen. Schieck, Eur. Phys. J. A 44, 321–354 (2010)]
[Deltuva and Fonseca, Phys. Rev. C 81 (2010)]
• Trajectories control of the fusion products
• United efforts on the practical use of the polarized fusion
Persistence of the Polarization in a Fusion Process
[J.-P. Didelez and C. Deutsch. Few-Body Conference, Bonn (2009)]
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History
B.P. Ad’jasevich, V.G. Antonenko
Measurement of the polarization
correlation coefficients in reactions
2H(d,
p)3H and 2H(d, n)3He
at low energies.
1976
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The Quintet suppression factor
QSF 
0 
 1,1
0
1
2 1,1  4 1,0   0,0  2 1,1 
9
Direct experiment required!
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Experiment layout
3
2+
He (0.8 MeV),
3 +
H (1.0 MeV)
Polarized Atomic Beam Source
I ~ 1 ∙ 1016 a/s
11
2
Target density ~ 10 a/cm
Vector polarization: ± 0.7
ABS
d 0 (0.1 eV)
dd-polarimeter
or LSP
d

r0 r
d d ®
2
He  n  e
3
H  pe
3
d  (1-32 keV)
Polarized Ion Source
Ion beam: I ≤ 20 μ A
(1.3 ∙ 1014 d/s)
Ebeam ≤ 32 keV
Vector polarization: ± 0.7
d 0 (0.1 eV)
Luminosity: 1.3∙1025 1/cm2 s
→ count rate: ~ 54/h (30keV)
→ 1 week of beam time
Ion
source
LSP
n (2.4 MeV),
p (3.0 MeV)
Lamb-Shift Polarimeter
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ABS (based on SAPIS ABS)
QMS
MFT
d
0
10
20
30
40
0
50 cm
ABS stages
1
3
4
1e-7 mbar
1e-6 mbar
IR
TV450
TMU1601
TMU1601
5e-5 mbar
3xTV450
TMU1001 TPH2200
5e-4 mbar
2
DUO030A
D30A
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D16B
D16B
~6000 L/s
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ABS dissociator
plasma
Cooled nozzle
(70-300K)
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Degree of dissociation and intensity measurements
Two-coordinate table
• QMS
• Compression tube
• Faraday cup
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POLIS Ion source
2010
Grounded
High potential (+10...+32kV)
0V
-100 V -5 kV
D0 (0.01 eV)
Cathode
d (10...32keV)
e- (100 eV) d (0.01...100 eV) d (5 keV)
Magnetic field 0.5 T
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POLIS. Control system.
• compact (high channel density)
• widely used in our systems at BNL, PSI, GSI
and AIRBUS test rig
• VERY old (is not supported 10 years)
• failed to work in KVI before departure
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POLIS. New control system (cooling + vacuum).
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POLIS. Current state.
 Water cooling [no central cooling system]
 Vacuum system [pressure : 2·10-7 mbar]
 Control system [vacuum and cooling only]
o Magnets
o Dissociator
o RF units
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Experimental hall
2009
2010
Sep 2011
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May 2011
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Experimental hall. Equipment layout
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Electronics platform
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Cooling system
System parameters:
• Liquid-air heatexchanger
• Cooling power: 100kW
• Coolant: water + 10% ethanol
• Flowrate: 1.4 l/s
• Temperature drop: 30-50°C
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Interaction chamber and detector system
Helmholtz
coils
Detector
system
Interaction
chamber
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Detector system. PIN diodes version.
4- detector setup with 44% filling
~300 Hamamatsu Si PIN photodiodes (S3590)
• 1cm2 active area
• 300um depletion layer
• good energy resolution (17keV for 1MeV Carbon ions at RHIC)
Proof of principle:
L. Kroell.
Diploma thesis, 2010.
FZJ – RWTH.
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Detector system
Surface Barrier Detector
4- detector setup with 65% filling
50 square detector elements (33x33mm)
800 SBD cells (7x7mm)
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Detector test bench
Vacuum
chamber
Detector
Preamplifier
Bleeding
valve
O scillo sco p e
a
H2
PC
Turbopump
Forepump
Alpha-source:
239Pu + 240Pu = 80.4%
238Pu + 241Am = 19.6%
234U
+
235U
+
238U
241Am
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Surface Barrier Detector. Energy resolution.
Alpha-source:
234U+235U+238U
∆E~35keV
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Surface Barrier Detector. Dead layer measurements
SRIMM calculations for 4He ions in Au:
30keV shift => 100nm gold layer
Alphabeam
SBD
rotated by
45 deg
Alphasource
Aperture
of the
source
Alpha-source:
239Pu
30keV
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Surface Barrier Detector. Hydrogen effect
1100 mbar
hydrogen
10-3mbar continuous
Experiment condition: 10-4÷10-5mbar
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Readout electronics
CSP from ATLAS CSC [BNL]
Readout requirements:
 800 channels
 Total count rate ≤ 1kHz
 Standard interface (Ethernet?)
 Event synchronization for coincidence trigger
24 channel CSP
Detector
24 channel ADC board
ADC
Charge
Sensitive
Preamplifier
+
Shaper
FPGA
Concentrator
FPGA
ADC
ADC
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Working Plan


Infrastructure
December 2012
 Experimental hall preparation
March 2011
 Platform for electronics
May 2011
 Water cooling system
December 2012
Assemble and run the POLIS source
June 2013
 Mechanical assembling
June 2011
 Vacuum + water distribution system
March 2012
 Control system
February 2012
 Adjustments and tuning
February 2013
 Solid target experiment
June 2013
Upgrade of the SAPIS ABS
December 2013
 Vacuum system
December 2012
 Magnet system design
December 2012
 Dissociator design
March 2012
 Transition units design
March 2013
 ABS tests and tuning
December 2013
Detector system
December 2012
 Interaction chamber
April 2011
 Surface barrier detector measurements
September 2012
 Mechanical support design
Spring 2012
 Readout electronics design
Fall 2012
 Electronics production
December 2012









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Thank you!
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Hyperfine states
ABS
HFS after
Sextupole 1
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
MFT
--1-4
3-4
3-4
3-4
1-4
1-4
HFS after
Sextupole 2
1, 2, 3
2, 3
1, 2
1, 2
1, 2
2, 3
2, 3
85% value
SFT
WFT
HFS after ABS
Pz
Pzz
Pz
Pzz
Beam
--------2-6
2-6
3-5
------on
-------
1, 2, 3
2, 3
1, 2
3, 4
1, 6
3, 6
2, 5
+1/3
0
+2/3
-2/3
+5/6
+1/6
-1/6
-1/3
-1
0
0
+0.5
-0.5
-0.5
0.272
-0.02
+0.561
-0.561
+0.714
+0.145
-0.145
-0.332
-0.85
-0.02
+0.02
+0.434
-0.391
-0.459
0
1
2
3
4
5
6
POLIS
HFS after
Sextupole 1
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
1, 2, 3
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MFT
--1-4
3-4
3-4
3-4
1-4
1-4
HFS after
Sextupole 2
1, 2, 3
2, 3
1, 2
1, 2
1, 2
2, 3
2, 3
75% value
SFT
WFT
HFS after ABS
Pz
Pzz
Pz
Pzz
Beam
--------2-6
2-6
3-5
------on
-------
1, 2, 3
2, 3
1, 2
3, 4
1, 6
3, 6
2, 5
0
-0.5
+0.5
-1
+1
0
0
0
-0.5
-0.5
+1
+1
+1
-2
0
-0.375
+0.375
-0.75
+0.75
+0.02
-0.02
0
-0.375
-0.375
+0.75
+0.75
+0.75
-1.5
0
1
2
3
4
5
6
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Count rate
Energy,
keV
10
20
30
40
50
60
70
80
90
100
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CrossCount rate
section, mb
1/hr
0.09
0.273
1.161
2.667
4.651
6.927
9.237
11.38
14.08
16.44
4
13
54
125
218
324
432
533
659
769
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Beam time
(10000), h
Beam time
(10000), days
2374
783
184
80
46
31
23
19
15
13
98.9
32.6
7.7
3.3
1.9
1.3
1.0
0.8
0.6
0.5
30
Data situation
Tagishi et al.; Phy. Rev. C
46 (1992) 1155-1158
[Analysing Powers:
2H(d,p)3H, solid target]
Becker et al.
Few Body Sys. 13 (1992)
[Analysing Powers]
Imig et al.
Phys.Rev. C 73 (2006)
[Spin-Transfer Koeff.]
All experiments were performed at solid targets
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The Formula
Spins of both deuterons
are aligned:
Only pz(qz) and pzz(qzz) ≠ 0
Only beam is polarized:
(pi,j ≠ 0, qi,j = 0)
σ(ϴ,Φ) = σ0(ϴ) · {1 + 3/2 Ay(ϴ) py
+ 1/2 Axz(ϴ) pxz
+ 1/6 Axx-yy(ϴ) pxx-zz
+ 2/3 Azz(ϴ) pzz }
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Unpolarized cross sections
  2 H d , n 3 He 
10
, mb
  2 H d , p 3 H 
1
0.1
0
20
40
60
80
100
120
Ed, keV
R. E. Brown, N. Jarmie, Phys. Rev. C 41 N4 (1990)
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Photomultiplier
Polarization measurement
B
B
B
B
B
t
Spin filter
Ionization
of atoms
Spin axis
rotation
Ions to
metastable
atoms
Spin
separation
120
120
te or
Pz = +1
Pzzteor= +1
100
80
mI=–1
te or
Pz = -1
teor
Pzz = +1
mI=+1
550
600
650
700
750
800
850
500
140
Pz(Ly- a) = 0
Pzz(Ly- a) = +0.72
WFT 1-4
SFT 2-6
100
mI=+1
mI=–1
te or
Pz = 0
Pzz teor= +1
80
60
mI=0
600
650
700
750
800
850
500
550
600
650
700
750
Magnetic field, a.u.
Magnetic field, a.u.
Pz = 0.73±0.05
Pz = –0.82±0.06
Pzz = 0.77±0.06
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te or
Pz = 0
teor
Pzz = -2
80
mI=–1
mI=+1
40
Magnetic field, a.u.
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mI=0
100
60
40
550
Pz(Ly- a) = -0.06
Pzz(Ly- a) = -1.09
WFT 1-4
SFT 3-5
120
mI=0
40
40
500
80
60
mI=–1
mI=0
60
100
Pz(Ly- a) = -0.76
Pzz(Ly- a) = +0.57
MFT 3-4
WFT 1-4
2-3
Ly-α
spectrum
Emission
of photons
N(Ly-a)
mI=+1
Quenching Faraday
Cup
chamber
120
140
N(Ly-a)
N(Ly-a)
Cs cell
Pz (Ly- a) = +0.68
Pzz(Ly- a) = +0.68
MFT 3-4
SFT 2-6
160
140
Wien filter
N(Ly-a)
Atomic
beam from
the ABS
Ionizer
800
850
500
550
600
650
700
750
800
850
Magnetic field, a.u.
Pzz = –1.17±0.08
34
Deuterium polarization
1
2
3
4
Vector polarization
Pz
1
1
6
2
mF
W/W
F=3/2
0
1:
2:
3:
4:
5:
6:
+3/2
+1/2
-1/2
-3/2
-1/2
F=1/2 +1/2
-2
mj=+1/2
mj=+1/2
mj=+1/2
mj=-1/2
mj=-1/2
mj=-1/2
0.5
mI=+1
mI=0
mI=-1
m I=-1
m I=0
m I=-1
2
0
3
-0.5
5
4
5
6
-4
4
2
0
6
Pzz 
4
0.01
8
=B/Bc
Pz 
-1
Pzz
N m I  1  N m I  1
0.1
1
 = B/Bc
10
Tensor polarization
1
1
+
4
0.5
N m I  1  N m I  0  N m I  1
6
0
1  3N mI 0
5
-0.5
N m I  1  N m I  0  N m I   1
3
-1
2
-1.5
-2
0.01
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0.1
1
 = B/Bc
10
35
Initial detector system
• 4- rotational gimbal support
• step motors with good angular resolution (~0.01 degree)
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