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F. M. Nunes NSCL, Michigan State University

Recent developments in the study of halo breakup. F. M. Nunes NSCL, Michigan State University. In collaboration with: Neil Summers (MSU) and Ian Thompson (Surrey). halo06. structure versus reactions. data = reaction x structure.

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F. M. Nunes NSCL, Michigan State University

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  1. Recent developments in the study of halo breakup F. M. Nunes NSCL, Michigan State University In collaboration with: Neil Summers (MSU) and Ian Thompson (Surrey) halo06

  2. structure versus reactions data = reaction x structure Usually not this simple: reaction and structure are entangled! halo06

  3. breakup and driplines Importance of breakup halo06

  4. low energy continuum experiments 11Be(p,p’)10Be+n [Shrivastava et al, PLB 596 (2004) 54] halo06

  5. 23O(Pb,Pb)22O+n+g [Nociforo et al, PLB 605 (2005) 79] low energy continuum experiments 9Be(17C, 16C g)X [Maddalena et al., PRC63(01)024613] halo06

  6. f is single particle/cluster wavefunction defined by potential Vvc fixed by binding energy for bound states resonances and scattering phase shifts for continuum l = core-valence relative angular momentum j = projectile total angular momentum breakup with CDCC: three body reaction • Projectile treated as 2-body system • 3-body Hamiltonian for reaction valence r R fix VcT and VvT from elastic scattering core target halo06 Summers @ NSCL2004

  7. Evc 20 0 s1/2 p1/2 p3/2 d3/2 d5/2 f5/2 f7/2 continuum discretization • Discretize continuum into bins • average wavefuntion over a bin with weight wi(k) • label the quantum numbers • for each bin by a i,lj wi(k) chosen so that the bin wavefunctions are real and normalized correctly using exc g.s. halo06 Summers @ NSCL2004

  8. CDCC equations • We have N coupled channels, each labeled by the set of quantum numbers • Solve set of radial coupled equations • Where the coupling potential from state a to state a’ is and the cluster target potentials include both Coulomb and Nuclear parts halo06 Summers @ NSCL2004

  9. 9Li(d,p)10Li(continuum) • H.B. Jeppesen et al., Nucl. Phys. A 748, 374 (2005). 26Ne(d,p)27Ne(continuum) • Obertelli et al., Phys. Letts B 633, 33 (2006) CDCC results for breakup 6Li breakup into d+4He 11Be breakup into n+10Be • N. Keeley and K. Rusek, Phys. Letts B 375, 9 (1996). • K. Rusek and K.W. Kemper, Phys.Rev.C 61, 034608 (2000). • C. Signorini et al., Phys. Rev. C 67, 044607 (2003). • J.A. Tostevin et al., Phys. Rev. C 66, 024607 (2002). • M. Takashina, et al., Phys.Rev.C 67, 037601 (2003). • A. Shrivastava et al., Phys. Lett. B596, 54 (2004). 6He breakup into nn+4He 15C breakup into n+14C • K. Rusek and K.W. Kemper, Phys.Rev.C 61, 034608 (2000). • T. Matsumoto, et al., Phys.Rev.C 70, 061601(R) (2004). • K. Ogata et al., Phys. Rev. C 73, 051602 (2006). • J.A. Tostevin et al., Phys. Rev. C 66, 024607 (2002). 7Be breakup into 3He+4He • N.C. Summers and F.M. Nunes, Phys. Rev.C 70, 011602(R) (2004). 8B breakup into p+7Be • F.M. Nunes and I.J. Thompson, Phys.Rev.C59, 2652 (1999). • B. Davids, et al., Phys.Rev.C 63, 065806 (2001). • J.A. Tostevin, F.M. Nunes, and I.J. Thompson, Phys.Rev.C 63, 024617 (2001). • J. Mortimer, I.J. Thompson, and J.A. Tostevin, Phys.Rev.C 65, 064619 (2002). • A. Moro et al., Phys. Rev. C 67, 047602 (2003). • T. Egami, et al., Phys.Rev.C 70, 047604 (2004). halo06

  10. mistake? halo06

  11. lj x 0+ 10Be r n I core excitation: eXtended CDCC halo06 [Summers, Nunes and Thompson, PRC 73 (2006) 031603R]

  12. 0+ 2+ lj 0+ 0+ 0+ 2+ x r I breakup of 11Be projectile fully coupled halo06

  13. 0+ 2+ lj 0+ 2+ 0+ 0+ x r I breakup of 11Be Dynamical excitation halo06

  14. lj x r I coupled channel model for 11Be coupled channel equation (i=l,j,I) core matrix elements = rotational model deformation of the core introduced via Rws halo06 [Nunes, Thompson and Tostevin, NPA 703 (2002) 593]

  15. continuum discretization • Discretize coupled channel continuum into bins quantum numbers for each bin by n  l,j,I halo06

  16. parallelized for each channel J parallelized • Dimension: NR=400-5000 radial steps • NC=50-1800a channels • NJ=30-200 J channels • Memory ~ NR.NC2 • Time ~ NR.NC3 .NJ • Code in F90 + MPI • Our present limit on the cluster is memory per node! computational problem • Second order coupled differential equation (enhanced numerov method) a (L,Jp,Jt,J,i,n) • We have a very very large number of coupling potentials to calculate halo06

  17. applications of XCDCC • breakup on a protons p(11Be,10Be+n+g)p @ E~60 MeV/u elastic+inelastic+transfer+breakup • breakup on a light target 9Be(11Be,10Be+n+g) 9Be @ E~60 MeV/u knockout • breakup on a heavy target at intermediate energies 208Pb(11Be,10Be+n+g) 208Pb @ E~40-60 MeV/u inelastic+breakup halo06

  18. Breakup on a heavy target @ E=40 MeV/A NR=5000 NC=500 NJ=100 NCPUS=4 walltime=5.5 d mem=65Gb Breakup on a protons @ E=40 MeV/A NR=400 NC=1800 NJ=30 NCPUS=16 walltime=4 d mem=120Gb computation details for HPC-cluster Breakup on 9Be @ E=60 MeV/A [Summers, Nunes and Thompson, PRC74, 014606 (2006)] under the approximation of no spin of the neutron NC halo06

  19. breakup of 11Be on 9Be 9Be(11Be,10Be)X @ E=60 MeV/A Comparison with other models CDCC measurement at MSU: neutron was not detected Includes stripping as well as breakup halo06 [Summers, Nunes and Thompson, PRC 73 (2006) 031603R]

  20. breakup of 11Be Stripping is not sensitive to deformation • Eikonal model including dynamical rotational excitations of 16C core • Inclusive cross section of rotational states of 16C • Assumed 17C(3/2+) [1d5/22+] ground state - pure single particle state with excited 2+ core • Enhanced breakup cross section due to deformed 16C+Target interaction halo06 [Batham, Thompson and Tostevin, PRC71 064608 (2005)]

  21. breakup of 11Be 9Be(11Be,10Be)X @ E=60 MeV/A Stripping cross section taken from eikonal calculations (J.A. Tostevin 2005) XCDCC breakup Data: Aumann et al., PRL84, 35 (2000) halo06 [Summers, Nunes and Thompson, PRC 73 (2006) 031603R]

  22. data: Shrivastava et al., Phys. Lett. B 596 (2004) 54. elastic 11Be+p data: Lapoux et al, GANIL halo06

  23. data: Shrivastava et al., Phys. Lett. B 596 (2004) 54. breakup 11Be on p halo06

  24. inelastic 11Be+Pb GANIL halo06 Data: Pain et al., GANIL

  25. inelastic 11Be+Pb halo06 Data: Pain et al., GANIL

  26. Conclusions • XCDCC provides an important step forward for understanding reactions with exotic beams • can be applied to a wide range of energies • includes nuclear and Coulomb on equal footing • consistent core excitation is also now possible • results for 11Be show that is has predictable power • still some discrepancies to understand… Experimentalists: Need less integrated data!! Experimentalists: elastic! elastic! elastic! Theorists: Need better structure model for projectile!! halo06

  27. Only possible due to: Neil Summers (Rutgers) Thanks halo06

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