March 2007 1
SPIRAL2 - Weizmann-Soreq-Louvain
18Ne
GANIL
Louvain la Neuve
March 2007 2
SPIRAL2 - Weizmann-Soreq-Louvain
Secondary neutrons + fission
BUT
Also light RIB’s
March 2007 3
SPIRAL2 - Weizmann-Soreq-Louvain
Accelerator artist view
176 MHz 3.8 m 1.5 MeV/u
M/q2
1st cryostat 6 SC HWR 176 MHz 0=0.09
2nd – 6th cryostats 40 SC HWR 176
MHz 0=0.15
40 MeV x 2 mA p / d RF SC linac
March 2007 4
SPIRAL2 - Weizmann-Soreq-Louvain
ECR Ion Source, LEBT and RFQ in situ
The SARAF accelerator
at Soreq, Israel.
Winter 2007
March 2007 5
SPIRAL2 - Weizmann-Soreq-Louvain
Fusion Reactions in the Sun:The CNO cycle
14O
17F
(,p)
…..
Proposed at GANIL
March 2007 6
SPIRAL2 - Weizmann-Soreq-Louvain
Mass accretion from a companion into a neutron star (black hole).
Role of 14O, 15O and 18Ne in the physics
of x-ray bursts
4He(15O,)19NEM. Wiescher et al. Erice Conference, 2007
J.L. Fisker et al., arXiv:astro-ph/070241
March 2007 7
SPIRAL2 - Weizmann-Soreq-Louvain
X-Ray Bursts and the “rp” process
The rp process and x-ray bursts - site of nucleo-synthesis
These movies simulate an x-ray burst and the rapid-proton capture (“rp”) process. The calculation begins at T9=T/10^9 K=40 with only neutrons and protons. As time progresses and the temperature drops below T9=10, nucleons assemble into 4He nuclei then into heavier mass nuclides. Once T9 falls below about 4, the QSE among the heavy nuclei begins to break down. Charged-particle reactions freeze out, and flow to higher mass number occurs via nuclear beta decay. This is the classical r-process phase.
March 2007 8
SPIRAL2 - Weizmann-Soreq-Louvain
The Astrophysical Journal, 650 (2006) 332J.L. Fisker et al.The Importance of 15O() 19Ne to X-Ray Bursts and Superbursts
Arxive-ph/0702412 Feb. 2007
J.L. Fisker et al.
Experimental measurements of the 15O( )19Ne reaction rate vs.
observations of type I X-ray bursts
Nuclear Physics A 718, (2003) 605
B. Davids et al.
Alpha-decay branching ratios of near-threshold states in 19Ne and the
astrophysical rate of 15O(α,γ)19NePRC 67 065809 (2003)
K. E. Rehm et al.
Branching ration of the 4.033 MeV 3/2+ state in 19Ne
Nuclear Physics A 688 (2001)465c.
S. Cherubini et al.
The 15O()19Ne reaction using a 18Ne radioactive beam
Partial sample of representative papers
March 2007 9
SPIRAL2 - Weizmann-Soreq-Louvain
A first experimental approach to the 15O + elastic scattering - Eur. Phys. J. A27, 183 (2006)
F. Vanderbist, P. Leleux, C. Angulo, E. Casarejos, M. Couder, M. Loiselet, G. Ryckewaert,
P. Descouvemont, M. Aliotta, T. Davinson, Z. Liu, and P.J. Woods
Recent experiments have determined (or put limits to ) for levels in 19Ne up to 5.092 MeV excitation energy. A conclusion is that a direct measurement of the 15O(, )19Ne
reaction in the region of astrophysical interest is currently impossible: 15O beams of intensity larger than 1011 pps on target would be required indeed to measure the 15O(a, )19Ne
cross-section in inverse kinematics in the energy region surrounding the first state above threshold, at 4.033 MeV….
March 2007 10
SPIRAL2 - Weizmann-Soreq-Louvain
14N(d,2n)14O cross section and yield 14N(d,n)15O cross section and yield for a 2 mA deuteron beam for a 2 mA
deuterons beam
But, extraction of atomic oxygen…
Long-learned lesson:
“orders-of-magnitude improvement in sensitivity of measurement –
enhanced understanding and possibilities”.
March 2007 11
SPIRAL2 - Weizmann-Soreq-Louvain
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79 81
Alpha Energy (MeV)
Cro
ss S
ectio
n (m
b)
0.0E+00
5.0E+09
1.0E+10
1.5E+10
2.0E+10
2.5E+10
3.0E+10
Yie
ld (a
tom
s/se
c) (I
nten
sity
0.1
mA
) Alice Yield [at/s]
O16(a,2n)18Ne
0.0
0.5
1.0
1.5
2.0
2.5
15 17 19 21 23 25 27 29 31 33 35 37 39 41
Proton Energy (MeV)
Cro
ss S
ectio
n (m
b)
0.0E+00
1.0E+11
2.0E+11
3.0E+11
4.0E+11
5.0E+11
6.0E+11
7.0E+11
8.0E+11
9.0E+11
Yie
ld (ato
ms/s
ec) (In
ten
sity 2
mA
)
Alice Yield [at/s]
F19(p,2n)18Ne
Tentative results
Lower yield, but, better extraction..
March 2007 12
SPIRAL2 - Weizmann-Soreq-Louvain
The beam (from Mats Lindroos – CERN)Production of an intense collimated neutrino (anti neutrino) beam directed at neutrino detectors via decay of accelerated radioactive ions
Decay
RingISOL target & Ion source
SPL
CyclotronsStorage ring and fast cycling synchrotron
6He 6Li e-18Ne 18Fe+
PS
SPSTo the French Alps
March 2007 13
SPIRAL2 - Weizmann-Soreq-Louvain
EURISOL INTERNATIONAL ADVISORY PANEL : .…“no progress has been made with the study of alternative production schemes
of 6He and 18Ne using low energy beams and strongly recommends that this study be completed…. The outcome of this study is an essential ingredient for the analysis whether it is technically feasible to decouple EURISOL and the beta-beams completely
March 2007 14
SPIRAL2 - Weizmann-Soreq-Louvain
Two stage production scheme
1 cm
40 MeV d5 mA
200 kWL=5 cm D=5 cm
5 cm
R=5 cm
9Be
fast n
Primary target
Secondary target
7Li(d,xn)
9Be(n,)6He
9Be(n,2n)8Be
Target:
C, Be, Li..
March 2007 15
SPIRAL2 - Weizmann-Soreq-Louvain
6He production (n,) cross section
0
20
40
60
80
100
120
0 2 4 6 8 10
neutron energy (MeV)
Cro
ss s
ecti
on
(m
b) Bass 1961
Savilev 1958Stelson 1957Stelson 1957MCNP
9Be(n,)6He
0
100
200
300
400
500
600
700
0 5 10 15 20
n energy (MeV)
Cro
ss s
ectio
n (m
b)
0.0E+00
5.0E+11
1.0E+12
1.5E+12
2.0E+12
2.5E+12
3.0E+12
3.5E+12
n flu
x pe
r 2
mA
d (
s-1)
9Be(n,2n)
9Be(n,)6He
n in Be target
Production yield of the order of 1013 6He per 1 mA d@40 MeV
Remember also 11B(n,)8Li
March 2007 16
SPIRAL2 - Weizmann-Soreq-Louvain
8Li energies of interestE(8Li [MeV])
3
6
March 2007 17
SPIRAL2 - Weizmann-Soreq-Louvain
R&D Steps
Via neutron converter – 6He, 8Li, ..
Simulations – Geant4, MCNP – PRODUCTION rate of ~1013/mA!!!
Converter design
Target design – Extraction (Be fibers, “microballs..)
Direct production – 14,15O, 18Ne,..
Design of targets (heat) for direct production (O and Ne);
materials (gas?), …
Extraction. Nitrogen is “bad”. Perhaps C02? M. Loiselet, LLN
12C(3He,n)14O and 12C(4He,n)15O Experiment: Beam, Team, Detectors (RMS-like, Si ball, EXOGAM..)…
March 2007 18
SPIRAL2 - Weizmann-Soreq-Louvain
Towards a full proposal – objectives and milestones.
2007-2009 Proposal to FP7 (Task 7.1) . Towards establishing a true collaboration.
Initial target design. R&D studies of both n-converter and direct production.
2009-2011 Target (s) manufacturing. Parameters for experimental setup.
2012-……. SPIRAL-II
March 2007 19
SPIRAL2 - Weizmann-Soreq-Louvain
SUMMARY
Presented ideas for light radio-nuclei production and use at SPIRAL2
Scientific Case
Calculations and simulations exist – but much more R&D needed
“Road Map” towards a full experiment
OPEN COLLABORATION – participation welcome!!
March 2007 20
SPIRAL2 - Weizmann-Soreq-Louvain
g.s.
‘2000
Type II Supernovae 8Li(,n)11B
March 2007 21
SPIRAL2 - Weizmann-Soreq-Louvain
MCNP 6He yield simulatio
n
Li
1 cm
2 mA80 kW
L=5 cm D=5 cm
5 cm
R=5 cm
9Be
fast n
Primary target
Secondary target
7Li(d,xn)
9Be(n,)6He
9Be(n,2n)8Be
0
5E+12
1E+13
1.5E+13
2E+13
2.5E+13
2 3 4 5 6
Be target radius (cm)
6H
e yi
eld
(at
m/s
)
D=5 cmD=10 cm
Simulated by Keren Lavie
Assuming:
1. a source target of solid Beryllium in place of liquid Li.
2. Secondary Be target at natural density.
March 2007 22
SPIRAL2 - Weizmann-Soreq-Louvain
Typical X-ray bursts:
• 1036-1038 erg/s• duration 10 s – 100s• recurrence: hours-days• regular or irregular
Frequent and very brightphenomenon !
(stars 1033-1035 erg/s)
March 2007 23
SPIRAL2 - Weizmann-Soreq-Louvain
Production of 14O
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40
Proton Energy (MeV)
Cro
ss S
ecti
on
(m
b)
0.0E+00
2.0E+11
4.0E+11
6.0E+11
8.0E+11
1.0E+12
1.2E+12
1.4E+12
Yie
ld (
ato
ms/
sec)
(In
ten
sity
2m
A)
CS [mb] CS Fit Yield [at/s]
14N(p,n)14O
March 2007 24
SPIRAL2 - Weizmann-Soreq-Louvain
sm = 3•10-19 [/eV], but…..
March 2007 25
SPIRAL2 - Weizmann-Soreq-Louvain
neutron flux in secondary target
0.0E+00
5.0E-04
1.0E-03
1.5E-03
2.0E-03
2.5E-03
3.0E-03
3.5E-03
4.0E-03
4.5E-03
5.0E-03
0 10 20 30 40 50
neutron enrgy (MeV)
n f
lux
per
init
ial n
(1/
cm2)
total0-1 cm4-5 cm9-10 cm
x
y
z
(0,0,0)
10cm
5cm Ben-Source
MCNP
K. Lavie
100% natural density
March 2007 26
SPIRAL2 - Weizmann-Soreq-Louvain
flux cross section overlap
0
100
200
300
400
500
600
700
0 5 10 15 20
n energy (MeV)
Cro
ss s
ectio
n (m
b)
0.0E+00
5.0E+11
1.0E+12
1.5E+12
2.0E+12
2.5E+12
3.0E+12
3.5E+12
n flu
x pe
r 2
mA
d (
s-1)
9Be(n,2n)
9Be(n,)6He
n in Be target
March 2007 27
SPIRAL2 - Weizmann-Soreq-Louvain
0.000
0.002
0.004
0.006
0.008
0.010
0 2 4 6 8 10
Position along the Be target (cm)
n 1.5
-15
Me
V fl
ux (
1/n
ini/c
m2)
100 % natural density Be target
production efficiency as function of Be target slide
MCNP
K. Lavie
March 2007 28
SPIRAL2 - Weizmann-Soreq-Louvain
Production of other isotope
0.1
1.0
10.0
100.0
1000.0
0 5 10 15 20
neutron energy (MeV)
Cro
ss s
ectio
n (m
b)
11B(n,p)11Be11B(n,a)8Li
0.1
1.0
10.0
100.0
1000.0
0 5 10 15 20
neutron energy (MeV)
Cro
ss s
ectio
n (m
b)
19F(n,p)19O19F(n,a)16N
]/[107.1 8138 sLiLidt
dN
Analytical calculation
March 2007 29
SPIRAL2 - Weizmann-Soreq-Louvain
Production of other isotope
0.1
1.0
10.0
100.0
1000.0
0 5 10 15 20
neutron energy (MeV)
Cro
ss s
ectio
n (m
b)
23Na(n,p)23Ne23Na(n,a)20F
0.1
1.0
10.0
100.0
1000.0
0 5 10 15 20
neutron energy (MeV)
Cro
ss s
ectio
n (m
b)
27Al(n,p)27Mg27Al(n,a)24Na
March 2007 30
SPIRAL2 - Weizmann-Soreq-Louvain
A new idea ….
There is a very noticeable lack of accelerators for STABLE BEAMS at
HIGH CURRENT. There is now even a separate European network for
such present and future facility.
Say, one installs at the SARAF a high-q ECR source and then one can
obtain beams of 240 MeV 12C, 320 MeV 16O etc. at hundreds of A
Build a high-efficiency- large solid angle Recoil Mass Separator or a
gas-filled magnet for nuclear structure and astrophysics.
To be explored…(!?)
March 2007 31
SPIRAL2 - Weizmann-Soreq-Louvain
0
1
2
3
4
5
6
7
8
9
10
8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40
Deuteron Energy (MeV)
Cro
ss S
ectio
n (m
b)
0.0E+00
5.0E+11
1.0E+12
1.5E+12
2.0E+12
2.5E+12
3.0E+12
3.5E+12
4.0E+12
Yie
ld (ato
ms/s
ec) (In
ten
sity 2
mA
)
AliceEmpireIIAlice Yield [at/s]EmpireII Yield [at/s]
14N(d,2n)14O
March 2007 32
SPIRAL2 - Weizmann-Soreq-Louvain
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
18 20 22 24 26 28 30 32 34 36 38 40
Proton Energy (MeV)
Cro
ss S
ectio
n (m
b)
0.0E+00
5.0E+12
1.0E+13
1.5E+13
2.0E+13
2.5E+13
3.0E+13
3.5E+13
4.0E+13
Yie
ld (ato
ms/s
ec
) (In
ten
sity 2
mA
)
Alice Alice-fit Yield [at/s]
160(p,pn)15O
0.0
20.0
40.0
60.0
80.0
100.0
120.0
140.0
160.0
180.0
200.0
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40
Deuteron Energy (MeV)
Cro
ss S
ectio
n (m
b)
0.0E+00
5.0E+12
1.0E+13
1.5E+13
2.0E+13
2.5E+13
Yie
ld (ato
ms/s
ec) (In
ten
sity 2
mA
)
Alice Alice-fit Yield [at/s]
14N(d,n)15O
March 2007 33
SPIRAL2 - Weizmann-Soreq-Louvain
Primary target fast n
spectrum
IFMIF S.P.Simakov et al.
2002
<En>=15 MeV
March 2007 34
SPIRAL2 - Weizmann-Soreq-Louvain
Accelerator layout
RFQ
PSM Module 2 Module 3 Module 4 Module 5 Module 6
MEBT
176 MHz
3.8 m
1.5 MeV/u
M/q2
1st cryostat
6 SC HWR
176 MHz
0=0.09
2nd – 6th cryostats
40 SC HWR
176 MHz
0=0.15
40 MeV x 2 mA p / d RF SC linac
March 2007 35
SPIRAL2 - Weizmann-Soreq-Louvain
March 2007 36
SPIRAL2 - Weizmann-Soreq-Louvain
March 2007 37
SPIRAL2 - Weizmann-Soreq-Louvain
0
100
200
300
400
500
600
700
0 5 10 15 20
n energy (MeV)
Cro
ss s
ectio
n (m
b)
0.0E+00
5.0E+11
1.0E+12
1.5E+12
2.0E+12
2.5E+12
3.0E+12
3.5E+12
n flu
x pe
r 2
mA
d (
s-1)
9Be(n,2n)
9Be(n,)6He
n in Be target
SiteRef.Production rate (6He/s)
Available for experiment (6He/s)
SARAF (2mA)This work2.4∙1013 *3∙1011
Beta-beam]25[6.3∙10128∙1011
Ganil-SPIRAL I]26[9∙107
Dubna-DRIB]27[1.5∙105
Louvain-la-Neuve]28[5.3∙106
Table 1 – comparison of 6He production yield for different laboratories• Assume the transmission efficiency for 6He extraction ionization and transport is ~ 1% [25].
March 2007 38
SPIRAL2 - Weizmann-Soreq-Louvain
Model dependence of the neutrino-deuteron disintegration cross sections at
low energieshttp://il.arxiv.org/abs/nucl-th/0702073v1
March 2007 39
SPIRAL2 - Weizmann-Soreq-Louvain
EURISOL INTERNATIONAL ADVISORY PANEL- Recent Report:
…“no progress has been made with the study of alternative production schemes of 6He and 18Ne using low energy beams and strongly recommends that this study be completed within the next year. The outcome of this study is an essential ingredient for the analysis whether it is technically feasible to decouple EURISOL and the beta-beams completely”.
March 2007 40
SPIRAL2 - Weizmann-Soreq-Louvain
Next step in simulation
Optimization: By adding a Be reflector √ As function of Be target density,
structure Including construction metals As function of L, D and R
L D
R
March 2007 41
SPIRAL2 - Weizmann-Soreq-Louvain
And Now What??.....
6He and the magnetic moment of the neutrino
Interest
Target NO Post-acceleration results
8Li(,n)11B and Type II Supernovae
14O(,p)17F and 15O(,)19Ne and x-ray bursts - nucleo-synthesis
Interest
Interest
Target
Target Post-acceleration
Post-acceleration
results
results
March 2007 42
SPIRAL2 - Weizmann-Soreq-Louvain
March 2007 43
SPIRAL2 - Weizmann-Soreq-Louvain
Present Status – SARAF Phase I – March ‘07
Building ready
Source and LEBT ready
RFQ installed and being conditioned
SC resonators installed in cryostat, individually tested,
waiting for final test of entire module.
First beam at ~4-5 MeV – Summer ’07
March 2007 44
SPIRAL2 - Weizmann-Soreq-Louvain
Beam Intensity = 2 mA (protons, deuterons) ; 0.2 mA (alphas) Proton Deuteron Alpha
5
40
5
40
5
40
Energy(MeV) Target
product Yield(a/s)
product
Yield(a/s)
product
Yield(a/s)
product
Yield(a/s)
product
Yield(a/s)
product
Yield(a/s) He6 5.09E+11 Li8 3.63E+11 Li8 1.56E+13 Li9 4.18E+08
Li7 Be7 2.11E+11 Be7 1.27E+13 Be7 1.59E+13 Be10 1.90E+11 N13# 9.31E+12 Be7 9.62E+11 N13 2.58E+12 Li8 3.32E+09 Be7 1.49E+02 Be10 5.40E+08 Be7 3.63E+08 C11 3.89E+10
B8 2.34E+11 Be11 6.50E+05 C14 2.96E+10 C10 1.76E+10 B8 4.72E+08 N13 4.46E+08 C11 3.13E+13 B12 5.90E+12 O14 5.51E+09 N11 2.21E+08 C11 6.68E+12 O15 6.37E+11 N12 1.86E+12 N12 2.58E+11
C12 N13# 7.50E+12
# - Yields are not including the half life of isotopes #
Yield Calculations: Sergei Vaintraub, HUJI
6He, 8Li and others also via a d+ 7Be neutron converter; the 11B(n,)8Li and 9Be(n,)6He reactions
80
March 2007 45
SPIRAL2 - Weizmann-Soreq-Louvain
Examples of Reactions with RNB’s for Astrophysics
• 8B(p,)9C
• 8B(,p)11C
• 9C(,p)12N
• 11C(p,)12N
March 2007
SPIRAL2 - Weizmann-Soreq-Louvain
11C(p,)12N, S(E) = E (E) exp(2)
Direct Capture is important at stellar energies except for the places of resonances , 2+, E
x=0.960 MeV and 2- 1.191
E0=0.030, E
0=0.020 MeV for CNO E
0=0.18, E
0=0.16 MeV for Novae