Nuclear Physics and Astrophysics at CERN

1. Nuclear Physics and Astrophysics at CERN Isao Tanihata (TRIUMF/ANL) Details of physics interests and methods for studies have been extensively presented. Necessity of ISOLDE/REX-ISOLDE and n-TOF has been presented by many speakers. Almost complete summary has given yesterday by Jürgen. I will try to give a review for persons outside this room.

2. My view • Nuclear physics is at a corner where a new paradigm is waiting behind the corner. • It is now become possible to combine experimental data in laboratories and astrophysical observations for understanding the synthesis of elements in universe and understanding stellar objects and phenomena. • CERN/ISOLDE facility has been providing crucial information and is expected to provide important information for such studies, and thus needs continuing operation and upgrading.

3. U Ra Beginning of nuclear physics Beginning of element synthesis 1985 Nuclear Physics beginning and future より重い元素

4. Studies of Radioactive Nuclei • To understand nuclear structure and reactions in whole range of nuclei by an unified view. • To understanding the origin of elements. • To give essential constraints on the standard model and beyond. • To expand applications based on nuclear science.

5. To understand the nuclear structures and reactions in whole range of nuclear chart • All the aspect of nuclear interactions in the nuclear structure is amplified at the driplines. A. Bonaccorso • New structure and new phenomena • Neutron halos, • Neutron skins • Covalent bond molecular states • Soft mode of collective motion • Change of magic numbers • New development of nuclear models • Green function monte calro • Anti-symmetrised molecular dynamics • No-core shell model • Cluster monte-carlo • Relativistic mean field • Continuume shell model, Gamow model M. Ploszajczak Interaction between bound and unbound states Granularity in nucleus Change of interactions New interactions

6. Constraints for nuclear models some important ingredients are missing! G. Bollen

7. What is the most important interactions for nuclear matter (saturation property) Tensor force! It is also extremely important for binding of light nuclei. (Argonne model) <V(4He)> ~ -152 MeV <VT>~ -70 MeV by Akaishi Why tensor force is not included explicitly in most models? Also three-body force?

8. 0d5/2 0d5/2 Otsuka et al. PRL 87 (01) 82502. stable nuclei and unstable nuclei Amplification of hidden interaction! tensor? three-body? other? ? ? Studies in different mass and N/Z nuclei may reveal hidden interactions!

9. Astrophysics (nucleosynthesis & star evolution) • Big bang to r-process <---> start of nuclear physics (20 century physics) • Nuclear processes are the most important in elements synthesis • Necessary data (mass, T1/2, excited states, reaction rates…) are essential data also for nuclear physics. • Era of more direct comparison between astronomical observations and nuclear physics is coming. (gamma-ray astronomy. As an example.. • Studies of specific variables or reactions as well as the general properties of nuclei are necessary. • Approaches are different • Today’s most important data will be known soon. • Today’s uninteresting data may be the most desirable tomorrow.

10. S-process is not known accurately! • Uncertainty in cross section is still very large. • Accurate (n, g) cross sections is necessary s= 37.0±3.2? 26.1±2.5? 12.5±0.4? mb

11. Advantage of RIB for Elementally Physics • Variety of samples appropriate to the specific need. • Selection of spin-parity, selection of mass, selection of Z, selection of u/d ratio • Highly developed methods • Ion trap, laser manipulation, beta-NMR, • Examples • Ft value of 0+ ->0+ super-allowed beta decay • Beta-neutrino correlation • Beta angular correlation • Use of isospin? • . and..

12. Polarized Beta Emitter (T=1/2 super allowed transitions) CVC in unsaturated spin system. ft = f(Gv<1>, GA<>) A =g(Gv<1>, GA<>,P)

13. Accelerated RIB (REX-ISOLDE) T. Nilsson • Direct measurements of nuclear cross sections of astrophysical relevance. • High-intensity RIB of energy up to 10A MeV provides various opportunity for nuclear structure (bound and unbound states) studies. • Coulomb excitation • Fusion reaction • Transfer reactions • Warning: single particle transfer reaction for spectroscopic factor may not be as efficient as the fragmentation method. • Developments of detecting system is extremely important. • Efficient targets. • Large solid angle large angle charged particle detectosr. • Efficient high efficiency g-ray detectors. • A forward spectrometer for determination of the final state.

14. Exchange existing 7-gap with IH accelerating structures Additional 9-gap accelerating structure 2003 2004 2006-7 3.1 MeV/u 4.3 MeV/u A < 85 A < 145 26-gap IH-resonator 7-gap IH IH2 1.55 MeV/u 3.75 MeV/u 202.56 MHz T. Nilsson 2.2 MeV/u A < 45 RIBs reaching the Coulomb barrier

15. Many facilities in the world. Is ISOLDE necessary?

16. ISOLDE facility is absolute necessity because • ISOL-type RIB facility provide high-quality beams. • ISOLDE can provide high-intensity RIB of energy relevant to nuclear structure and astrophysics studies. • ISOLDE is providing beams of more than 70 elements! • In ISOL facility an extraction of one new element needs hard and difficult development. • TRIUMF ~26 (Alkali metals and Lanthanides), Oakridge~23 • A versatile elements at ISOLDE is the most important resource of nuclear science. • New invention in experimental methods have been made at ISOLDE.. ISOLTRAP, MISTRAL • A large number of eligible physicists is another important resource of nuclear science.

17. Conclusion • Nuclear structure physics need a new paradigm. • Unified description of structure from elementary interactions. D. Vretenar • Astrophysics based on experimental data is now a reality. • They have to be recognized as new direction of physics. Reductionism ----> Wholism REX-ISOLDE, ISOLDE, n-TOF are important for such development of physics and science.