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GANIL Louvain la Neuve 18 Ne March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 1 GANIL Louvain la Neuve 18 Ne March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 1

Secondary neutrons + fission BUT Also light RIB’s March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain Secondary neutrons + fission BUT Also light RIB’s March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 2

Accelerator artist view 40 Me. V x 2 m. A p / d RF Accelerator artist view 40 Me. V x 2 m. A p / d RF SC linac 2 nd – 6 th cryostats 40 SC HWR 176 MHz b 0=0. 15 176 MHz 3. 8 m 1. 5 Me. V/u M/q 2 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 1 st cryostat 6 SC HWR 176 MHz b 0=0. 09 3

ECR Ion Source, LEBT and RFQ in situ The SARAF accelerator at Soreq, Israel. ECR Ion Source, LEBT and RFQ in situ The SARAF accelerator at Soreq, Israel. Winter 2007 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 4

…. . Fusion Reactions in the Sun: The CNO cycle 17 F 14 O …. . Fusion Reactions in the Sun: The CNO cycle 17 F 14 O March 2007 (a, p) SPIRAL 2 - Weizmann-Soreq-Louvain v Proposed at GANIL 5

Mass accretion from a companion into a neutron star (black hole). § Role of Mass accretion from a companion into a neutron star (black hole). § Role of 14 O, 15 O and 18 Ne in the physics of x-ray bursts 4 He(15 O, )19 NE March 2007 M. Wiescher et al. Erice Conference, 2007 J. L. Fisker et al. , ar. Xiv: astro-ph/070241 SPIRAL 2 - Weizmann-Soreq-Louvain 6

X-Ray Bursts and the “rp” process These movies simulate an x-ray burst and the X-Ray Bursts and the “rp” process These movies simulate an x-ray burst and the rapid-proton capture (“rp”) process. The calculation begins at T 9=T/10^9 K=40 with only neutrons and protons. As time progresses and the temperature drops below T 9=10, nucleons assemble into 4 He nuclei then into heavier mass nuclides. Once T 9 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 rprocess phase. n The rp process and x-ray bursts site of nucleosynthesis March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 7

Partial sample of representative papers The Astrophysical Journal, 650 (2006) 332 J. L. Fisker Partial sample of representative papers The Astrophysical Journal, 650 (2006) 332 J. L. Fisker et al. The Importance of 15 O(a, g) 19 Ne to X-Ray Bursts and Superbursts Arxive-ph/0702412 Feb. 2007 J. L. Fisker et al. Experimental measurements of the 15 O(a, g )19 Ne 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 astrophysical rate of 19 Ne and the 15 O(α, γ)19 Ne PRC 67 065809 (2003) K. E. Rehm et al. Branching ration Ga/Gg of the 4. 033 Me. V 3/2+ state in 19 Ne Nuclear Physics A 688 (2001)465 c. S. Cherubini et al. The March 2007 15 O(a, g)19 Ne reaction using a 18 Ne radioactive beam SPIRAL 2 - Weizmann-Soreq-Louvain 8

A first experimental approach to the 15 O + a elastic scattering - Eur. A first experimental approach to the 15 O + a elastic scattering - Eur. Phys. J. A 27, 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 Ga (or put limits to Ga) for levels in 19 Ne up to 5. 092 Me. V excitation energy. A conclusion is that a direct measurement of the 15 O(a, g)19 Ne reaction in the region of astrophysical interest is currently impossible: 15 O beams of intensity larger than 1011 pps on target would be required indeed to measure the 15 O(a, g)19 Ne cross-section in inverse kinematics in the energy region surrounding the first state above threshold, at 4. 033 Me. V…. March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 9

Long-learned lesson: “orders-of-magnitude improvement in sensitivity of measurement – enhanced understanding and possibilities”. 14 Long-learned lesson: “orders-of-magnitude improvement in sensitivity of measurement – enhanced understanding and possibilities”. 14 N(d, 2 n)14 O cross section and yield for a 2 m. A deuteron beam 14 N(d, n)15 O cross section and yield for a 2 m. A deuterons beam But, extraction of atomic oxygen… March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 10

Tentative results Lower yield, but, better extraction. . March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain Tentative results Lower yield, but, better extraction. . March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 11

The b beam (from Mats Lindroos – CERN) Production of an intense collimated neutrino The b beam (from Mats Lindroos – CERN) Production of an intense collimated neutrino (anti neutrino) beam directed at neutrino detectors via b decay of accelerated radioactive ions SPL 6 He 18 Ne Decay ISOL target & Ion source Cyclotrons Storage ring and fast cycling synchrotron March 2007 e -n 18 Fe+n 6 Li SPS Ring To the French Alps PS SPIRAL 2 - Weizmann-Soreq-Louvain 12

EURISOL INTERNATIONAL ADVISORY PANEL: “…. no progress has been made with the study of EURISOL INTERNATIONAL ADVISORY PANEL: “…. no progress has been made with the study of alternative production schemes of 6 He and 18 Ne 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 SPIRAL 2 - Weizmann-Soreq-Louvain 13

Two stage production scheme Secondary target Primary target 9 Be Target: R=5 cm C, Two stage production scheme Secondary target Primary target 9 Be Target: R=5 cm C, Be, Li. . 1 cm fast n 9 Be(n, 2 n)8 Be 9 Be(n, a)6 He 40 Me. V d 5 m. A 200 k. W 5 cm L=5 cm D=5 cm 7 Li(d, xn) March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 14

6 He production (n, a) cross section Production yield of the order of 1013 6 He production (n, a) cross section Production yield of the order of 1013 6 He per 1 m. A [email protected] Me. V Remember also 11 B(n, a)8 Li March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 15

E(8 Li [Me. V]) 8 Li energies of interest 6 3 March 2007 SPIRAL E(8 Li [Me. V]) 8 Li energies of interest 6 3 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 16

R&D Steps Via neutron converter – 6 He, 8 Li, . . v Simulations R&D Steps Via neutron converter – 6 He, 8 Li, . . v Simulations – Geant 4, MCNP – PRODUCTION rate of ~1013/m. A!!! v Converter design v. Target design – Extraction (Be fibers, “microballs. . ) Direct production – 14, 15 O, 18 Ne, . . v Design of targets (heat) for direct production (O and Ne); materials (gas? ), … v Extraction. Nitrogen is “bad”. Perhaps C 02? M. Loiselet, LLN 12 C(3 He, n)14 O and 12 C(4 He, n)15 O Experiment: Beam, Team, Detectors (RMS-like, Si ball, EXOGAM. . )… March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 17

Towards a full proposal – objectives and milestones. v 2007 -2009 Proposal to FP Towards a full proposal – objectives and milestones. v 2007 -2009 Proposal to FP 7 (Task 7. 1). Towards establishing a true collaboration. Initial target design. R&D studies of both n-converter and direct production. v 2009 -2011 Target (s) manufacturing. Parameters for experimental setup. v 2012 -……. SPIRAL-II March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 18

SUMMARY v Presented ideas for light radio-nuclei production and use at SPIRAL 2 v SUMMARY v Presented ideas for light radio-nuclei production and use at SPIRAL 2 v Scientific Case v Calculations and simulations exist – but much more R&D needed v “Road Map” towards a full experiment v OPEN COLLABORATION – participation welcome!! March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 19

Type II Supernovae 8 Li(a, n)11 B ‘ 2000 g. s. March 2007 SPIRAL Type II Supernovae 8 Li(a, n)11 B ‘ 2000 g. s. March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 20

Secondary target Li Primary target 9 Be R=5 cm fast n 1 cm 9 Secondary target Li Primary target 9 Be R=5 cm fast n 1 cm 9 Be(n, 2 n)8 Be 9 Be(n, a)6 He 2 m. A 80 k. W 5 cm L=5 cm D=5 cm MCNP 6 He yield simulation 7 Li(d, xn) 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 SPIRAL 2 - Weizmann-Soreq-Louvain 21

Typical X-ray bursts: • 1036 -1038 erg/s • duration 10 s – 100 s Typical X-ray bursts: • 1036 -1038 erg/s • duration 10 s – 100 s • recurrence: hours-days • regular or irregular Frequent and very bright phenomenon ! (stars 1033 -1035 erg/s) March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 22

Production of 14 O March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 23 Production of 14 O March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 23

msm = 3 • 10 -19 [mn/e. V], but…. . March 2007 SPIRAL 2 msm = 3 • 10 -19 [mn/e. V], but…. . March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 24

neutron flux in secondary target 100% natural density MCNP K. Lavie March 2007 SPIRAL neutron flux in secondary target 100% natural density MCNP K. Lavie March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 25

flux cross section overlap March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 26 flux cross section overlap March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 26

production efficiency as function of Be target slide MCNP K. Lavie March 2007 SPIRAL production efficiency as function of Be target slide MCNP K. Lavie March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 27

Production of other isotope Analytical calculation March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 28 Production of other isotope Analytical calculation March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 28

Production of other isotope March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 29 Production of other isotope March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 29

v. A new idea …. v There is a very noticeable lack of accelerators v. A new idea …. v 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. v Say, one installs at the SARAF a high-q ECR source and then one can obtain beams of 240 Me. V 12 C, 320 Me. V 16 O etc. at hundreds of m. A v 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 SPIRAL 2 - Weizmann-Soreq-Louvain 30

March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 31 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 31

March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 32 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 32

Primary target fast n spectrum <En>=15 Me. V IFMIF S. P. Simakov et al. Primary target fast n spectrum =15 Me. V IFMIF S. P. Simakov et al. 2002 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 33

Accelerator layout 40 Me. V x 2 m. A p / d RF SC Accelerator layout 40 Me. V x 2 m. A p / d RF SC linac 176 MHz 1 st cryostat 2 nd – 6 th cryostats 3. 8 m 6 SC HWR 40 SC HWR 1. 5 Me. V/u 176 MHz M/q 2 b 0=0. 09 b 0=0. 15 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 34

March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 35 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 35

March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 36 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 36

Site Ref. Production rate (6 He/s) Available for experiment (6 He/s) SARAF (2 m. Site Ref. Production rate (6 He/s) Available for experiment (6 He/s) SARAF (2 m. A) This work 2. 4∙ 1013 * 3∙ 1011 Beta-beam [25] 6. 3∙ 1012 8∙ 1011 Ganil-SPIRAL I [26] 9∙ 107 Dubna-DRIB [27] 1. 5∙ 105 Louvain-la-Neuve [28] 5. 3∙ 106 March 2007 Table 1 – comparison of 6 He production yield for different laboratories • Assume the transmission efficiency for 6 He extraction ionization and transport is ~ 1% [25]. SPIRAL 2 - Weizmann-Soreq-Louvain 37

v Model dependence of the neutrino-deuteron disintegration cross sections at low energies March 2007 v Model dependence of the neutrino-deuteron disintegration cross sections at low energies March 2007 http: //il. arxiv. org/abs/nucl-th/0702073 v 1 SPIRAL 2 - Weizmann-Soreq-Louvain 38

EURISOL INTERNATIONAL ADVISORY PANEL- Recent Report: “… no progress has been made with the EURISOL INTERNATIONAL ADVISORY PANEL- Recent Report: “… no progress has been made with the study of alternative production schemes of 6 He and 18 Ne 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 SPIRAL 2 - Weizmann-Soreq-Louvain 39

Next step in simulation Optimization: n By adding a Be reflector √ n As Next step in simulation Optimization: n By adding a Be reflector √ n As function of Be target density, structure n Including construction metals n As function of L, D and R R L March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain D 40

And Now What? ? . . . v 6 He and the magnetic moment And Now What? ? . . . v 6 He and the magnetic moment of the neutrino Interest v 8 Li(a, n)11 B Interest Target NO Post-acceleration results and Type II Supernovae Target Post-acceleration results v 14 O(a, p)17 F and 15 O(a, )19 Ne and x-ray bursts - nucleo-synthesis Interest March 2007 Target Post-acceleration SPIRAL 2 - Weizmann-Soreq-Louvain results 41

March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 42 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 42

Present Status – SARAF Phase I – March ‘ 07 § Building ready § 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 Me. V – Summer ’ 07 March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 43

Yield Calculations: Sergei Vaintraub, HUJI 80 6 He, 8 Li and others also via Yield Calculations: Sergei Vaintraub, HUJI 80 6 He, 8 Li and others also via a d+ 7 Be neutron converter; the 11 B(n, a)8 Li and 9 Be(n, a)6 He reactions March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 44

Examples of Reactions with RNB’s for Astrophysics • 8 B(p, g)9 C • 8 Examples of Reactions with RNB’s for Astrophysics • 8 B(p, g)9 C • 8 B(a, p)11 C • 9 C(a, p)12 N • 11 C(p, g)12 N March 2007 SPIRAL 2 - Weizmann-Soreq-Louvain 45

11 C(p, )12 N, S(E) = E (E) exp(2 ) Direct Capture is important 11 C(p, )12 N, S(E) = E (E) exp(2 ) Direct Capture is important at stellar energies except for the places of resonances , 2+, Ex=0. 960 Me. V and 2 - 1. 191 E 0=0. 030, E 0=0. 020 Me. V for CNO E 0=0. 18, E 0=0. 16 Me. V for Novae 3/16/2018 SPIRAL 2 - Weizmann-Soreq-Louvain