The Ring Branch. Nuclear Reactions at. Mass- and Lifetime Measurements. off Exotic Nuclei. Internal Targets. Electron and p. Experiments: Scattering

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1 stochastic cooling Exotic nuclei from Super-FRS Degrader for fast slowing down The Ring Branch TOF Detector MCPs E anode ion B CR Electron cooler NESR secondary electrons Experiments: Mass- and Lifetime Measurements Electron and p Scattering off Exotic Nuclei Nuclear Reactions at Internal Targets C + CsI foil Gas Target and Detector Tagging of reaction products p Si strip array Scintillator Gas jet Beam Schottky pickup eacollider Heavy ions e - Reaction zone Electron spectrometer e -

2 The High Energy Branch Reactions with Relativistic Radioactive Beams:

3 Expected Production Rates r-process presently known nuclei

4 III. Nuclear Reactions with Radioactive Beams at FAIR The EXL and R3B Proposals EXL: EXotic Nuclei Studied in Light-Ion Induced Reactions at the NESR Storage Ring Ring Branch R3B: Reactions with Relativistic Radioactive Beams High Energy Branch

5 Perspectives at the GSI Future Facility FAIR regions of interest: t single-particle structure evolution (new magic 28 numbers, TERRA INCOGNITA towards the driplines for medium heavy and heavy nuclei p physics interest: matter distributions (halo, skin ) new shell gaps, spetroscopic factors) 20 known exotic nuclei e NN correlations, pairing and clusterization phenomena new collective modes (different deformations for p and n, giant resonance strength) parameters of the nuclear equation of state in-medium interactions in asymmetric and low-density matter astrophysical r and rp processes, understanding of supernovae unknown exotic pathways nuclei of stellar nucleosynthesis

6 Light-Ion Induced Direct Reactions elastic scattering (p,p), (, ), nuclear matter distribution (r), skins, halo structures inelastic scattering (p,p ), (, ), deformation parameters, B(E2) values, transition densities, giant resonances charge exchange reactions (p,n), ( 3 He,t), (d, 2 He), Gamow-Teller strength transfer reactions (p,d), (p,t), (p, 3 He), (d,p), single particle structure, spectroscopic factors spectroscopy beyond the driplines neutron pair correlations neutron (proton) capture cross sections knock-out reactions (p,2p), (p,pn), (p,p 4 He) ground state configurations, nucleon momentum distributions, cluster correlations

7 R3B: Reactions with Relativistic Radioactive Beams The setup The R 3 B experiment: a universal setup for kinematical complete measurements

8 EXL: EXotic Nuclei Studied in Light-Ion Induced Reactions at the NESR Storage Ring Heavy-Ion Spectrometer Electron cooler Neutrons / Charged Ejectiles Recoil Detector Gas jet Beam in Storage Ring ea-collider RIB s from the Super-FRS

9 Light-Ion Induced Direct Reactions elastic scattering (p,p), (, ), nuclear matter distribution (r), skins, halo structures inelastic scattering (p,p ), (, ), deformation parameters, B(E2) values, transition densities, giant resonances transfer reactions (p,d), (p,t), (p, 3 He), (d,p), single particle structure, spectroscopic factors, spectroscopy beyond the driplines, neutron pair correlations, neutron (proton) capture cross sections charge exchange reactions (p,n), ( 3 He,t), (d, 2 He), Gamow-Teller strength knock-out reactions (p,2p), (p,pn), (p,p 4 He) ground state configurations, nucleon momentum distributions for almost all cases: region of low momentum transfer contains most important information

10 Experiments to be Performed at Very Low Momentum Transfer Some Selected Examples Investigation of Nuclear Matter Distributions along Isotopic Chains: halo, skin structure probe in medium interactions at extreme isospin (almost pure neutron matter) in combination with electron scattering: separate neutron/proton content of nuclear matter method: elastic proton scattering at low q: high sensitivity to nuclear periphery Investigation of Giant Monopole Resonance in Doubly Magic Nuclei: gives access to nuclear compressibility key parameters of the EOS new collective modes (breathing mode of neutron skin) method: inelastic scattering at low q Investigation of Gamow-Teller Transitions: weak interaction rates for N = Z waiting point nuclei in the rp-process electron capture rates in the presupernova evolution (core collaps) method: ( 3 He,t), (d, 2 He) charge exchange reactions at low q

11 Kinematical Conditions for Light-Ion Induced Direct Reactions in Inverse Kinematics CM = 20 0 CM = Sn(p, p) E=740 MeV/u, E* = 0 MeV 18 C(, ) E=400 MeV/u, E* = 0 MeV 18 C(p, p') E=400 MeV/u, E* = 25 MeV 196 Pb(, ') E=400 MeV/u, E* = 15 MeV 196 Pb( 3 He, t) E=400 MeV/u, E* = 0 MeV 12 Be( 3 He, t) E=400 MeV/u, E* = 0 MeV 22 C(p, d) E=15 MeV/u, E* = 0 MeV 132 Sn(d, p) E=15 MeV/u, E* = 0 MeV CM = 5 0 CM = 5 0 CM = 5 0 required beam energies: E MeV/u (except for transfer reactions) required targets: 1,2 H, 3,4 He most important information in region of low momentum transfer low recoil energies of recoil particles need thin targets for sufficient angular and energy resolution Erecoil (MeV) CM = 1 0 EXL (, ) Points are: CM = 1, 5, 10 and 20 0 ( 3 He, t) lab (deg) (p,p)