Study of spin-isospin responses of radioactive nuclei with the background-reduced neutron spectrometer, PANDORA

The status of a project to measure spin-isospin responses of neutron drip-line nuclei using a new low-energy neutron detector, PANDORA (Particle Analyzer Neutron Detector Of Real-time Acquisition), is reported. The performance of PANDORA was characterized by the 6He(p,n)6Li reaction in inverse kinematics at the HIMAC facility in Chiba. Observation of the strong transition to the ground state in 6Li is discussed. Preliminary results of 11Li(p,n)11Be and 14Be(p,n)14B experiments in inverse kinematics at RI Beam Factory (RIBF) of RIKEN Nishina Center are also presented including the exotic decay channel of 11Be→9Li + d. Details of the experimental setup based on PANDORA and the SAMURAI large-acceptance magnetic spectrometer, as well as the combined data-acquisition system are described. The neutron-gamma discrimination capability of PANDORA was evaluated, Figure-of-Merit (FoM) values higher than those found in the literature for similar materials were derived from experimental data

Study of Gamow-Teller giant resonance in ¹¹Li drip-line nucleus

Gamow-Teller (GT) transitions in an exotic neutron-rich nucleus 11Li have been measured via the 11Li(p,n)11Be reaction at 182 MeV/u in inverse kinematics at RI Beam Factory (RIBF) of RIKEN Nishina Center. The neutron detector array PANDORA and the SAMURAI spectrometer were used to detect recoil neutrons and decay products produced in the (p,n) reaction, respectively. Preliminary results of kinematic correlation of recoil neutrons, corresponding to GT transitions, are presented for several decay channels of 11Be reaction product. Fourteen decay channels with light-particle emission from 11Be excited states, including seven new channels, are identified, in addition to the non-particle-emission channel from 11Be ground or low-lying states.</p

Study of Gamow-Teller giant resonance in ¹¹Li drip-line nucleus

Gamow-Teller (GT) transitions in an exotic neutron-rich nucleus 11Li have been measured via the 11Li(p,n)11Be reaction at 182 MeV/u in inverse kinematics at RI Beam Factory (RIBF) of RIKEN Nishina Center. The neutron detector array PANDORA and the SAMURAI spectrometer were used to detect recoil neutrons and decay products produced in the (p,n) reaction, respectively. Preliminary results of kinematic correlation of recoil neutrons, corresponding to GT transitions, are presented for several decay channels of 11Be reaction product. Fourteen decay channels with light-particle emission from 11Be excited states, including seven new channels, are identified, in addition to the non-particle-emission channel from 11Be ground or low-lying states.</p