# [Triumf-seminars] TRIUMF Seminar today at 14:00

Thu May 31 05:00:00 PDT 2007

Date/Time: Thu 2007-05-31 at 14:00

Location:  Auditorium

Speaker:   Juris Svenne (University of Manitoba)

Title:     Coupled-channel Study of Scattering from and Structure of Light Unstable Nuclei

Abstract: An algebraic formulation of multi-channel scattering theory (MCAS) has been developed and applied to the study of nucleon scattering from light nuclei. The procedure allows inclusion of the Pauli principle, even when the target nucleus is defined by a collective model. Results for the scattering of both neutrons and protons from $^{12}$C compare favourably to data concerning bound states of the compound nucleus ($^{13}$C or $^{13}$N) with the same nucleon-nucleus interactions. Excellent concordance with data is achieved for total and differential scattering cross sections and analysing powers. This method has recently been extended to allow the calculation of nuclei away from the line of stability, even particle-unstable nuclei. These necessitated extending the procedure for treating the Pauli principle to include the concept of Pauli hindrance''. It is thus possible to account for three situations: Pauli allowed states (no Pauli violation could occur), Pauli blocked (excluding states where projectiles would scatter into already filled single-particle orbits of the target), or Pauli hindered (where projectiles go into partially filled orbits). MCAS results presented will include two systems involving unstable nuclei. From considering $p + ^{14}$O scattering, information extracted for the particle unstable $^{15}$F. Congruity is achieved with recent data that exhibit two shape resonances at low energy in scattering of radioactive $^{14}$O from hydrogen. Another study investigates all mass-7 nuclides between proton and neutron drip lines. Again using Pauli hindrance, a quite satisfactory account of all  these nuclei with only one and nucleon-nucleus interaction matrix for all. Finally, we have a new calculated result for the $^3$He($\alpha, \gamma$)$^7$Be Astrophysical S factor.

Stimulants available 15 minutes before the talk.

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