Study of Gamow-Teller transitions from 132Sn via the (p,n) reaction at 220 MeV/u in inverse kinematics

The charge-exchange ( p , n ) reaction at 220 MeV has been measured to extract the strength distribution of Gamow-Teller transitions from the doubly magic unstable nucleus 132 Sn. A recently developed experimental technique of measuring the ( p , n ) reaction in inverse kinematics has been applied to the study of unstable nuclei in the mass region around A ∼100 for the first time. We have combined the low-energy neutron detector WINDS and the SAMURAI spectrometer at the RIKEN radioactive isotope beam factory (RIBF). The particle identification plot for the reaction residues obtained by the spectrometer provides the clear separation of the CE reaction channel from other background events, enabling us to identify kinematic curves corresponding the ( p , n ) reaction. Further analysis to reconstruct the excitation energy spectrum is ongoing.