1. Nuclear break-up of exotic nuclei I History of the towing mode in stable nuclei the 40 Ar+ 58 Ni @ 40 MeV/A case IIThe TDSE calculation IIIThe case of the 11 Be break-up IVThe extension to borromean nuclei V Conclusions - Perspectives JassJass

2. Inelastic Channel-projectile=ejectile A A A A A A+1 AAAA InelasticScattering GR and multiphonons KnockOutPick-upBreak-up New mechanism ? Target Projectile 1 emitted particle 1 or several emitted particle(s) JassJass

3. Angular distribution of nucleon emitted in 58 Ni( 40 Ar, 40 Ar + n or p) p or n 58 Ni 40 Ar  lab JassJass Feeding of the first hole states of the daughter nucleus

4. t JassJass Action

5. What happens when a force acts on a mass for a given period of time ? F = m.x.. t c = d vpvp d  (r o. A 1/3 )= 4 fm v p = 10 +23 fm.s -1 t c = 4. 10 -23 s mF x x =. t c + x o. F m. F = 15 MeV.fm -1 x o = 0. x =. 15. 9. 10 +46 900.4. 10 -23 = 6.10 +22 fm.s -1 3 fm E ~ 40 MeV/A Right order of magnitude! JassJass Action

6. Nuclear break-up of exotic nuclei I History of the towing mode in stable nuclei the 40 Ar+ 58 Ni @ 40 MeV/A case IIThe TDSE calculation IIIThe case of the 11 Be break-up IVThe extension to borromean nuclei V Conclusions - Perspectives JassJass

7. H  = .  diagonalization  eigen states, eigen values Evolution of a one-particle wave function via the resolution of time dependent Schrödinger Evolution of a one-particle wave function via the resolution of time dependent Schrödinger H= p 2 2.m + U 0 1+e (r-r 0 ) a 0 Static solutions ^ JassJass J.A. S. D. Lacroix Ph. Chomaz Time dependent solutions ih d dt  = H   (t+dt) = e - i Hdt h  ( t ) H= p 2 2.m + U 0 target 1+e (r-r 0 (t)) a 0 + U 0 proj 1+e (r-r 0 (t)) a 0 and ^ FFT of  (x,t)... ^ proj target Split operator D.Lacroix et al. Nucl. Phys. A658 (1999) p273 Exact up to 2 sd order

8. The calculation includes : TDSE for a wave function in a moving potential diffraction (refraction!) through the nuclear potential single particle excitations to unbound states n-core excitations (!!) « shaking » of the core (Coulomb classical trajectory) The calculation does not include : spin-orbit, pairing No structure info core or target excitations (not excluded either) nucleon-nucleon dissipation quantum relative motion energy conservation Resolution of time dependent Schrödinger equation on a mesh non perturbative calculation proj target proj target JassJass

9. Evolution of a wave function via the resolution of time dependent Schrödinger Evolution of a wave function via the resolution of time dependent Schrödinger Initial wave function Towing Mode Target WS Projectile WS E inc = 44 MeV/A t = 0t = 130 fm/c JassJass

10. Initial Density Probability in the target potential at rest in the lab frame. Density probablility after the projectile has passed Fourier transform of the former density probability. y x pxpx pypy JassJass Same density probability after subtraction of the bound eigen states y x Angular distribution of the emitted particle Evolution FFT d  /d  (  )

11. 58 Ni( 40 Ar, 40 Ar+p or n) 2p calculation, b from 10 to 12 fm Plus flat background b=10 fm 40 Ar 58 Ni JassJass ~50° pxpx pypy 2s

12. Nuclear break-up of exotic nuclei I History of the towing mode in stable nuclei the 40 Ar+ 58 Ni @ 40 MeV/A case IIThe TDSE calculation IIIThe case of the 11 Be break-up IVThe extension to borromean nuclei V Conclusions - Perspectives JassJass

13. 11 Be break-up calculations WS potential to bound the 2s by 0.5 MeV Need to use a Coulomb trajectory : Weakly bound neutron Large Coulomb break up Runge Kuttar(t+dt) = r(t-dt) + 2.dt.p(t)/m p(t) = p(t-2dt) + 2.dt.F(t-dt)/m 13 fm 2000 80 15 1 Density of 2s Imaginary time evolution extract a stable eigen state (M.Fallot...) for the cartesian mesh Interpolation... Does not change when using N.Vinh Mau potential JassJass

14. Neutron angular distributions Au,Ti,Be ( 11 Be, 10 Be + n) @ 41 Mev/A Data from : R.Anne et al.,Nucl.Phys. A575 (1994) 125 M.Fallot, J.A.Scarpaci, D.Lacroix, Ph. Chomaz et J.Margueron, Nuclear Physics A700 (2002) 70 Large b (Coulomb break-up) = forward peaked emitted neutron Small b (nuclear break-up) = responsible for neutrons emitted at large angle neutron lab The nuclear break-up is fully reproduced by the interaction of the particle with the mean field of the target - no need of n-n interaction…. JassJass

15. JassJass 11 Be a halo nucleus Neutron bound by 0.504 MeV GS ( J  =1/2 + ): | GS>=  |2s 1/2  0 + > +  |1d 5/2  2 + > 10 Be n  2 (S 2s ) et  2 (S 1d ): spectroscopic factors 10 Be 2 + state of  2 =0.74 Ref: Auton et al. NP A 322(1970) 305 E  =3.37 MeV 

16. GANIL SPEG Primary beam of 13 C @ 75 A.MeV Secondary beam of 80000 11 Be/s @ 41 A.MeV. SISSI JassJass

17. Experimental set-up 48 Ti 11 Be 3 m3 m  n-detectors 10 Be SPEG Château de cristal 10 Be 48 Ti TDSE Calculation JassJass 11 Be 10 Be + n +  @ 41 MeV/A Experimental set-up & results  lab Our data 1994 data from R.Anne et al., Nucl. Phys. A575 (1994) 125. TDSE calculations M.Fallot et al., Nucl. Phys. A 700 (2001) 70-82. Neutron angular spectra

18. S 1d = 0,50 ± 0,20 S 1p = 3.9  in  coincidence V.Lima et al., Bormio 2004 V.Lima, Ph.D. Paris XI, oct 2004 V.Lima et al., in preparation 4*1p 0.5*1d S 2s = 0,47± 0,04 no -  Neutron energy spectra TDSE calc. 2s 11 Be 10 Be + n +  @ 41 MeV/A 10 Be 48 Ti 11 Be 3 m3 m  n-detectors 10 Be SPEG Château de cristal TDSE Calculation JassJass Experimental set-up & results

19. Break-up reactions ( 11 Be, 10 Be) @ 520 MeV/u Palit et al., PR. C 68, 034318 (2003) Large diversity of S 2s The G.S. of 11 Be Transfer reaction p( 11 Be, 10 Be)d: GANIL Fortier et al., PL B 461(1999)22-27 |GS> ~  |2s 1/2  0 + > +  |1d 5/2  2 + > S 2s ≈ 85-36% S 1d ≈ ?% Break-up reactions ( 11 Be, 10 Be) @ 60 MeV/u and eikonal models T. Aumann et al., P.R.L.84 (2000) 35-38 Our work B.Zwieglinski et al. Nucl.Phys.A315, 124 (1979) N.K.Timofeyuk et al. P.R.C59, 1545 (1999) DWBA excitation and break-up nucl. elect.

20. Nuclear break-up of exotic nuclei I History of the towing mode in stable nuclei the 40 Ar+ 58 Ni @ 40 MeV/A case IIThe TDSE calculation IIIThe case of the 11 Be break-up IVThe extension to borromean nuclei V Conclusions - Perspectives JassJass

21. Study of neutron correlations with nuclear break-up 6 He is an archetype of a Borromean nucleus ; high intensities most suitable nucleus to investigate new experimental approach and develop new theoretical tools Cigar configuration Zhukov et al., Phys. Rep. 231 (1993) 151 Di-neutron configuration JassJass three-body description expansions on hyperspherical harmonics coordinate space Faddeev approach

22. Some experiments on 6 He… Transfer reactions 4 He( 6 He, 6 He) 4 He dominated by di-neutron conf… Yu.Oganessian et al. (1999) : Dao T.Khoa and W.von Oertzen (2004) Radiative capture 6 He(p,  )x @ 40 MeV/A - no  + t decay large distance between the two neutrons… (cigar like) E.Sauvan et al. (2001) Coulomb break-up 6 He + C, Pb @ 30-60 MeV/A large distance between the two neutrons… (cigar like) Invariant mass ≠ interferometry … depending on impact parameter cuts… G.Normand et al. (2004) r n-n 7.7 fm, 9.4 fm F.M.Marques et al. (2000) r n-n 5.9 fm @ 240 MeV/A 6,8 He + Pb @ 700 MeV/A L.V.Chulkov et al. (2005) QFS dominates low lying 1 - states 3-6 MeV  core plus 2 or 4 neutrons 8 He = small 6 He + 2n No consensus on the n-n configuration Open to more experiments JassJass

23. Neutron angular emission Large impact parameters Coulomb break-up cigardi-neutron  n d  /d  60 ° 0°0° Small differences in relative angles G.Normand, PhD thesis 2004 F.M.Marques, PR C64, 2001 Measure neutrons at large angles Needs a theoretical development Small impact parameters Nuclear break-up cigardi-neutron  n d  /d  60 ° 0°0° di-neutron cigar extension of TDHF (TDDM) (M.Assie-D.Lacroix) JassJass

24. Set-up 65° Faraday cup Neutron wall Additional neutron detectors n n 5 mg/cm 2 Pb target 4 He Si det. High neutron angular coverage up to 90° : neutron wall + 20 additional detectors Si detector for 4 He covering from 5° to 15° 6 He 20 MeV/u

25. Nuclear break-up of exotic nuclei I History of the towing mode in stable nuclei the 40 Ar+ 58 Ni @ 40 MeV/A case IIThe TDSE calculation IIIThe case of the 11 Be break-up IVThe extension to borromean nuclei V Conclusions - Perspectives Reaction mechanism plays an important role in the break-up towing Mode, a spectroscopic tool need of good theoretical description to infer spectroscopic factors Development required for two-particle wave function evolution extension of TDHF - Marlène Assié, Denis Lacroix Possible application to cluster studies! observation of  emission in 40 Ca break-up JassJass