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Open questions and issues in nuclear astrophysics

Open questions and issues in nuclear astrophysics. Kerstin Sonnabend Darmstadt, Germany Presented by: Michael Hass, Weizmann, Israel. And the role of EURISOL…. CARINA C hallenges and A dvanced R esearch I n N uclear A strophysics. Carmen Angulo. Kerstin Sonnabend

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Open questions and issues in nuclear astrophysics

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  1. Open questions and issues in nuclear astrophysics Kerstin Sonnabend Darmstadt, Germany Presented by: Michael Hass, Weizmann, Israel And the role of EURISOL….

  2. CARINAChallenges and Advanced Research In Nuclear Astrophysics Carmen Angulo Kerstin Sonnabend Institut für Kernphysik, TU Darmstadt, Germany

  3. CARINA activities • Two CARINA workshops organized: • First workshop: „Perspectives in European Nuclear Astrophysics“, Parador d‘Aiguablava, Girona, Spain, June 8th - 10th, 2005 • 39 participants from ten countries • five review talks on astrophysical models (explosive burning and AGB/quiescent burning), nuclear models for astrophysics, experiments with RIB at LSF, and experiments at small facilities • short talks and discussions in working group sessions (plenary) • summary of the conclusions: • large variety of problems needs large variety of methods • specific tools needed for different nucleosynthesis scenarios • small-scale facilities as ‚feeders‘ to large-scale facilities • establish a ‚flagship‘ ISOL-type facility for nuclear astrophysics with gas targets, recoil separator, spectrometer, solid-state detectors, and g-ray detection systems available • find tentative lists of astrophysical sites and nuclear models for nuclear astrophysics

  4. CARINA activities • Second workshop: „Frontier Research in European Nuclear Astrophysics“, Spaulomont, Spa, Belgium, April 25th - 28th, 2007 • 37 participants from 13 countries • 21 talks and five discussions (plenary) • workshop explored opportunities for new European facilities • agreement that additional facilities, specifically for nuclear astrophysics, are warranted and needed • lively discussion over strategy: should it be a dedicated nuclear astrophysics proposal, or complementary to a general nuclear physics proposal? • possibilities include: nuclear astrophysics labs network, an underground accelerator, a dedicated nuclear astrophysics separator for capture reactions, reclamation of radioisotopes, ...

  5. Continuation of the CARINA network within FP7 • JRA-9 (P.J. Woods & M. Hass) • NA-15 (S. Marrone & F. Käppeler) • NA-16 (K. Sonnabend & C. Angulo) • and tasks of N-NA07 (Theory) related to Nuclear Astrophysics

  6. N-NA06:Nuclear Astrophysics Coordinator: K. Sonnabend, Darmstadt, Germany Task 1 – Explosive Nucleo-Synthesis P.J. Woods, Edinburgh, UK, M. Hass, Weizmann, Israel Task 2 - Reactions at Low Temperatures K. Sonnabend, Darmstadt, Germany Task 3 - Nucleo-Synthesis in neutron capture processes S. Marrone, INFN Bari, Italy Task 4 – Nuclear astrophysics annual meeting ENSAR meeting, Frankfurt, December 12th, 2007

  7. Novelty & Innovation • Concentrate on special issues of interdisciplinary field of research • Provide individual solutions for problems of special issues • Use already available infrastructures • Find and enhance synergetic effects • Integrate it all in annual meetings

  8. Task 2 - Reactions at Low Temperatures K. Sonnabend, Darmstadt, Germany • e.g. - Solar reactions • Not necessarily RIB • Smaller laboratories (local) • Underground possibilities (“a la LUNA”)

  9. The SNO (Sudbury Neutrino Observatory) Experiment A D2O Detector Elastic Mostly ne nx +e-nx+e- ne + d p + p + e- charge current Only ne nx + d p + n + nx neutral current All flavors YES!! PRL87, 071301 (2001) PRL 89, 011301 (2002) PRL 92, 181301 (2004) “SMOKING GUN”!!

  10. Current status of S17 - direct capture - determinations Recognized need for a new WI measurement at low energy… In progress… 7Be(p,g)8B “saga” not over yet…..

  11. Summary of Coulomb Dissociation S17Results F. Schümann et al. Phys. Rev. C 73, 015806 (2006) By Courtesy of T. Motobayashi

  12. ·  (7Be,8B) proton transfer at 12 MeV/u two targets: 10B: S17(0) = 18.4  2.5 eVb (PRL ’99) 14N: S17(0) = 18.0  1.8 eVb (PRC ’99; PRC ‘06) ·13C(7Li,8Li)12C at 9 MeV/u using mirror symmetry (PRC ‘03) S17(0) = 17.6  1.7 eVb Average: S17 =18.2  1.7 eVb S17astrophysical factor - ANC - (R. Tribble) Transfer Determine C2 by three approaches 8B breakup • JLM S17=17.4±2.1 eVb • “standard” S17=19.6±1.2 eVb • Ray S17=20.0±1.6 eVb Average: S17=18.7±1.9 eVb PRC ‘04

  13. Results and Fits New LUNA Activity Result - Phys. Rev. Lett. 97, 122502 (2006) S34(0) = 0.53(2)(1) keV-b B.S. Nara Singh et al., Phys. Rev. Lett. 93, 262503 (2004). No compelling need to assume Systematic difference between prompt and activity determinations • RMS ERNA in Bochum • Seattle

  14. Dedicated experiments to measure the 7Be EC lines: Borexino etc… SNO

  15. b.- Primordial 7Li –SBBN (A. Coc, Orsay)

  16. n_TOF/Astrophysics:present & future Task 3 - Nucleo-Synthesis in neutron capture processes S. Marrone, INFN Bari, Italy stefano.marrone@ba.infn.it www.cern.ch/n_TOF

  17. Nuclear Astrophysics Re/Os cosmo-chronometer Red Giants Nr= Nsolar – Ns Residual Method Supernovae stefano.marrone@ba.infn.it www.cern.ch/n_TOF

  18. The n_TOF-Ph2 experiments 2008 and beyond (*) endorsed by CERN Isolde-n_TOF Committee, execution in 2008 stefano.marrone@ba.infn.it www.cern.ch/n_TOF

  19. The second n_TOF beam line NewExperimentalArea (EAR-2) ~ 20 m present EAR-1 (at 185 m) Proton Beam Spallation Target • present EAR-1: Flight path ~185 m, Neutron Flux~106 n per proton bunch; High resolution in neutron energy. • new EAR-2: Flight path ~20 m at 90° with respect to p-beam; neutron flux enhanced by factor ~100; drastic reduction of backgrounds. stefano.marrone@ba.infn.it www.cern.ch/n_TOF

  20. Task 1 – Explosive Nucleo-Synthesis • Identification of the key reactions, including specification of the energy range and • precision required for future experimental studies (leading institute: Barcelona). • Identification of the key technical developments required to deliver the highest • priority radioactive beams to measure these reactions including exchange of • technical ideas and coordination, of how and where developments should be • best achieved (leading institute: Weizmann). • Identification of the key characteristics of design and construction of • novel detector and spectrometer systems to measure these reactions • including exchange of technical ideas and coordination of single activities • (leading institute: Edinburgh). • Determination of key features of nuclear properties, nuclear reactions, • and the nuclear equation of state for astrophysical simulations and their • experimental and/or theoretical verification (leading institute: Basel).

  21. Secondary neutrons + fission BUT Also light RIB’s And SARAF!

  22. Fusion Reactions in the Sun:The CNO cycle ….. 17F (a,p) 14O • Proposed at GANIL

  23. Mass accretion from a companion into a neutron star (black hole). • Role of 14O, 15O and 18Ne in the physics of x-ray bursts M. Wiescher et al. Erice Conference, 2007 J.L. Fisker et al., arXiv:astro-ph/070241 4He(15O,g)19NE

  24. X-Ray Bursts and the “rp” process The rp process and x-ray bursts - site of nucleo-synthesis Courtesy of Joint Inst. For Nuclear Astrophysics (US)

  25. Recent Experiments (in progress) ISOLDE experiment IS424 (Sept. ’07): (in collaboration with P.J. Woods et al.). • The use of a 17F beam from the upgraded REX-ISOLDE facility to study the • astrophysically important 14O(α,p)17F reaction in time reverse kinematics. • REX-ISOLDE + MINIBALL • Only ~ 103 17F/s On-line data of p-g coincidences – Indicating the 1st excited state of 17F

  26. GANIL experiment – accepted by GANIL PAC : (in collaboration with Marialuisa Aliotta et al.) Plan to investigate the direct 14O(a,p)17F reaction at four different energies in the energy region Ecm = 1.0-2.5 MeV Calculated total S(E) factor. Constructive (+) and destructive (-) interference between the Jpp=1- 6.15 MeV state and the direct l=1 partial wave contribution are shown.

  27. Long-learned lesson: “orders-of-magnitude improvement in sensitivity of measurement – enhanced understanding and possibilities”. 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…

  28. 8Li energies of interest E(8Li [MeV]) 6 3

  29. Examples of Reactions with RNB’s for Astrophysics • 8B(p,g)9C • 8B(a,p)11C • 9C(a,p)12N • 11C(p,g)12N

  30. Nucleosynthesis in AGB Stars - Maurizio M. Busso Perugia CNO, Ne-Na, Mg-Al Cycles Important experimental and theoretical work has addressed the CNO cycle…….. e.g. 14N(p,g)15O (see: Schroeder et al. 1987; Angulo et al. 2001) Runkle et al. 2002, Phys Rev C 66 Formicola et al. 2004, Phys. Lett. B. 591 Runkle et al. 2005, Phys Rev C 94 …. and of the hotter cycles of H-burning: e.g. for reacions on O isotopes and Na (leading to Mg-A) Fox et al. 2004, Phys. Rev. Lett. 93: 17O+p Rowlad et al. 2004 Phys Rev. Lett 93: 23Na+p

  31. RECENT LUNA ACHIEVEMENTS ON CNO H.P. Trautvetter, ECT Nuclear Astrop. Workshop, (Trento, May 2004)

  32. Ne-Na and Mg-Al ‘cycles’ (p,g) (p,a) (p,g) But; effects on higher nuclei (26Al) limited by minimal of 20Ne production (at least with NACRE): Arnould et al. 1999.

  33. Finances • each specialized task (1 - 3): 50 k€ • general annual meetings: 40 k€ • support of coordinator: 4 k€ • total costs: 194 k€

  34. General considerations to remember: - • It is nuclear structure after all - masses, Q values, lifetimes, • reaction theory, …. • Nuclear (astro) physics vs. “modeling” and “standard” astro. • Nuclear astrophysics as “motif” for many RIB facilities. • BUT • How much time would a Facility devote to these time-consuming experiments

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