Recent progress and developments for experimental studies with the SAMURAI spectrometer

The large acceptance spectrometer SAMURAI plays an important role in experiments at RIBF, RIKEN for studying exotic nuclei far from beta stability. We report here the investigation of the responses of the neutron detectors in the SAMURAI facility. The detection efficiency of a single neutron in the NEBULA neutron detector walls was determined to be 32.5 +/- 0.3(stat) +/- 0.9(syst)% by a measurement of the Li-7(p, n)Be-7(g.s. + 0.43 MeV) reaction at 200 MeV. The effect of multiple hits caused by a single neutron in three-wall configuration of the NeuLAND demonstrator and NEBULA have been investigated in the Ne-29(p, 2p) reaction at around 210 MeV/nucleon and analysis method has been developed enabling two or more neutron coincidence measurements. A simulation study for single and four neutron detection is reported. Finally, other recent progress and future perspectives are presented.