1 / 27

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.

esben
Download Presentation

F. M. Nunes NSCL, Michigan State University

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  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

More Related