Nuclear Reactions as a Tool for Structure Studies of Exotic Nuclei

H. Lenske

Institut für Theoretische Physik U. Giessen

• Low Energy Transfer Reactions

• Charge Exchange Reactions

• Fano-Resonances in Exotic Nuclei

• (Antiprotons as Probes for Neutron Skins)

• Summary and Outlook

Extraction and Extrapolation of Spectral Information, Location of

Driplines, -Decay, Reaction Rates … : Reaction Theory!

• Direct Reaction• Suppression of Compound Reactions• Particle Detection plus ray Detection• Spectral Distributions, Continuum

Transfer Reactions with Secondary Beams: Pickup/Stripping in Inverse Kinematics

H.L., G.SchriederEur.Phys.J. A2 (1998) 41

Low Energy Transfer Reactions with Exotic Nuclei

The 9Li+d 8Li+t Reaction @ REX-ISOLDE Data Tlab=2.36 AMeV

H.Jeppesen et al. , PLB (2006)

The 9Li+d 8Li+t Reaction @ REX-ISOLDE Theory and Data Tlab=2.36 AMeV

H. Jeppesen et al., PLB (2006)

C2S=0.89

C2S=0.34

C2S=1.33

Theory: 9Li+d 10Li+p @ Tlab=2 AMeV

10Li 9Li + n: Spectroscopy in the Continuum

Reaction Mechanism of 2n-Transfer

Two-Neutron Transfer Reactions

11B(7Li,7Be)11Be Reaction at Tlab=57 MeV

Experiment by the Catania Group at IPN-Orsay Tandem Lab

TEGTES )(Im

1)(

)()()()( 00 EVGEGEGEG

2121)()(

VVV

and CE Response by Continuum QRPA: Dyson Equation and Multipole Response

Functions

QRPA Fermi-type Beta-Response

QRPA GT-type Beta-Response

F. Cappuzzello, H.L. et al, NPA 739 (2004) 30

DWBA-Analysis of 11B(7Li,7Be)11Be at Tlab=57MeV

33 )2/(),()()(),(

prpppr iNNAa eEtpdEF

11B(7Li,7Be)11Be(1/2+,g.s.) 11B(7Li,7Be)11Be(5/2+,1.77)

33

1,0)2/(),()()(),(

prpppr i

NNAaopt eEtpdEU

11B(7Li,7Be)11Be Reaction at Tlab=57 MeV:NN Interactions and Cross Section

33 )2/(),(),()()(),(

prppppr iTNN

CNNAa eEtEtpdEF

The Neutron Halo in 19C:Transition from Mean-Field to Correlation

Dynamics

The DCP picture: Binding by Polarization Potential

H.L.,J. Prog.Part.Nucl. 561 (2003);C. Nociforo, H.L., Nucl.Phys (2006)

The s.p. shell model picture: Static Potential

√<r2>(1/2+) = 5.34 fm

S = 0.40

Shape and Size of 19C and 16O

√<r2>(1/2-) = 2.96 fm

S = 0.97

z

(x,y)

19C18C+n at Tlab=910AMeV on a

C-Target:

theo =69MeV/c

exp =68±3MeV/c

(-1n,theo)=192mb

(-1n,exp )=233±51mb

Correlation Dynamics in the Continuum: Fano-Resonances in 15C

~60…140keV

S. Orrigo, H.L., PLB (2006) in print

Summary and Outlook

• Nuclear Structure Nuclear Reactions

• Reaction Theory far off Stability

• Reaction Dynamics

• Elastic Channels Optical Potentials

• New Phenomena: Fano Resonances …

• Continuum Dynamics

• to be addressed: optical Potentials, Transition Form Factors, Reactions at Relativistic Energies (FAIR)

Contributors:

Sonja Orrigo, Nadia Tsoneva, Chiara Nociforo, F. Cappuzzello, C. Keil

The Binding Energy of Ni-Isotopes: HFB Binding

Energies

Non-relativistic HFB Calculations(D3Y G-Matrix: DME with 3-body forces)

Measuring Neutron Skins along Isotopic Chains (Ni,Sn…):

p + A Absorption at FAIR – AIC Proposal

P. Kienle, NMB 214 (2004) H.L., P. Kienle, nucl-th/0502065; PLB (2006)

Measuring Neutron Skins (Ni,Sn…): Antiproton Absorption on Exotic

Nuclei

H.L., P. Kienle, PLB (2006); nucl-th/0502065

(7Li,7Be) CE X-Sections and Beta-Response