1. Sep. 2003CNS Summer School Feb. 2003 50 分 => Talk なら 35 枚だが、 lecture だと少なめ？ 50 分 => Talk なら 35 枚だが、 lecture だと少なめ？

2. Sep. 2003CNS Summer School Nuclear-structure studies with fast exotic beams Tohru Motobayashi (RIKEN) Ring Cyclotron (1987) + RIPS (~1990) - RIKEN fast exotic beam or RI beam by projectile fragmentation v/c ~ 0.3 (40-90 MeV/nucleon) c.f. RIBF => 200-300 MeV/nucleon, wide range of nucl. “ In-beam ”  - and particle spectroscopy => nuclear structure of unstable nuclei magicity loss in n-rich nuclei with N=8, 20 => reactions involved in (explosive) nuclear burning solar neutrino production, novae burning

3. Sep. 2003CNS Summer School RIKEN Accelerator Research Facility and RI Beam Factory Project 135 MeV/nucleon for light nuclei 350 MeV/nucleon up to U 1st beam in 2006 under consideration 0 1 2

4. Sep. 2003CNS Summer School MSU RIKEN Coulomb excitation of N = 20 nuclei Disappearance of the sd-pf shell gap for 32 Mg and 30 Ne

5. Sep. 2003CNS Summer School RIKEN-I (94) RIKEN-2 (98) C.D.: insensitive to M1 resonance 1 + (M1) Coulomb dissociation of 8 B Solar neutrino production

6. Sep. 2003CNS Summer School How can we study nuclear structures with fast Radio-isotope (RI) beams ? 1) Direct reactions for nuclear-structure studies 2) RI beams of fragmentation scheme 3) Inverse kinematics 4) Two methods of spectroscopy Doppler-shifted g-rays Particle decays from unbound states 5) Some examples

7. Sep. 2003CNS Summer School direct reaction => nuclear structure information target = object  E PID bam = probe examples: (p,p ’ ), (d,p), … reaction channel: PID of ejectile excited level: E (  ) cross section => deformation single particle strength angular distribution => angular momentum direct (first-order) mechanism

8. Sep. 2003CNS Summer School 58 Ni(d,p) 59 Ni E =15 MeV (1962) distance along the focal plane (momentum) l - dependence of angular distribution 4 0 1 2 3

9. Sep. 2003CNS Summer School projectile fragmentation target projectile by Ong Hooi Jin  ~ 0 v ~ v beam wide range of (unstable) nuclei regardless of chemical properties E > 50 MeV/nucleon

10. Sep. 2003CNS Summer School inverse kinematics / methods of spectroscopy RI (beam) + target (probe) -----> projectile-like products  decays (bound) particle decays (unbound) ------>target-like products recoil particles target-  reaction-channel ID: PID of the projectile-like product state ID:  ray (Doppler-shifted) invariant mass reaction: inelastic (Couex, C.D., (p,p ’ ) … cex, fratmentation, knockout transfer

11. Sep. 2003CNS Summer School Advantage / disadvantage of fast RI beams poor (intensity) 0.1 - 10 5 pps dirty (emittance) 2cm , 1~2 deg. Spread high energy efficient setups good reactions (large  )  -ray measurement invariant mass thick targets forward focusing

12. Sep. 2003CNS Summer School Detector arrays

13. Sep. 2003CNS Summer School 300 pps

14. Sep. 2003CNS Summer School MSU RIKEN Coulomb excitation of N = 20 nuclei Disappearance of the sd-pf shell gap for 32 Mg and 30 Ne

15. Sep. 2003CNS Summer School Yanagisawa et al., Phys. Lett. B566 (2003)84 Yoneda et al., Phys. Lett. B566 (2003)84 Locations of 2 + / 4 + states of n-rich around N=20 - “ Island of inversion ” - 34 Mg (Z=12, N=22) Fragmentation of 36 Si (2x10 4 cps) 30 Ne (Z=10, N=20) proton inelastic 30 Ne (0.2 cps) 2+2+ 2+2+ 4+4+

16. Sep. 2003CNS Summer School counts 34 Si Gate: 2 + - 0 +  -  coincidence : newly assigned 34 Si + 2 H -> 34 Si +  + X Iwasa et al., Phys. Rev. C67 (2003) 064315 (2x10 4 cps) (Z=14, N=20)

17. Sep. 2003CNS Summer School 50 - 90 MeV/nucleon DALI HODO 8 B Coulomb dissociation DALI ( 208 Pb)

18. Sep. 2003CNS Summer School 8 B+ 208 Pb  7 Be+p+ 208 Pb (C.D.)  virtual photon theory or DWBA 8 B( ,p) 7 Be (abs.)  detailed balance 7 Be(p,  ) 8 B (capt.) large  thick target (intermediate energy) experiments with R.I. beams 8 B 208 Pb 7 Be p Coulomb dissociation Virtual photons c.f. Nakamura halo nuclei = Coulomb excitation to unbound states c.f. Mueller, Mueller, … spectroscopy

19. Sep. 2003CNS Summer School detailed balance virtual photon number (intermediate energy) thick target charged particle detection indirect i.e. nucl. force / higher order / E2 100 ~ 1000 Large yield but

20. Sep. 2003CNS Summer School E rel <= p p, p 7Be,  p-Be  E rel : Independent of  E in  E rel =200 keV p+X, T 0 =100 AMeV, E rel =1 MeV,  =0.5 deg.  v=1% kinematics

21. Sep. 2003CNS Summer School RIKEN-I (94) RIKEN-2 (98) C.D.: insensitive to M1 resonance 1 + (M1) Coulomb dissociation of 8 B Solar neutrino production

22. Sep. 2003CNS Summer School spectroscopy with fast exotic beams RI (beam) + target (probe) - inverse kinematics -----> projectile-like products  decays (bound) particle decays (unbound) ------>target-like products recoil particles target-  reaction-channel ID: PID of the projectile-like product good state ID:  ray (Doppler-correction) invariant mass reaction w. large  : inelastic (Couex, C.D., (p,p ’ ) … cex, fratmentation, knockout transfer forward focusing, thick target, efficient detectors =>