Silicon Tracker for Cluster-Knockout Reactions at Intermediate Energies

The cluster-knockout reaction project, ONOKORO, has been launched to elucidate the formation mechanism of clusters in atomic nuclei. For the inverse-kinetics cluster-knockout reaction experiments, a new detector array is under development to measure energies and angles of light ions emitted in the reactions. The silicon tracker tracks the particles with good angular and energy-loss resolutions. A performance test of the silicon strip detectors with a thickness of 100μm and a strip width of 100μm was performed using prototype silicon detectors. The mono-energetic proton and α-particle beams were irradiated on the silicon detectors. The energy-loss spectra in silicon detectors showed a good signal-to-noise ratio. The threshold level for signal detection is seven sigma of noise level. Their dynamic ranges were optimized wide enough to detect charge number Z= 1 and Z= 2 ions emitted in the cluster-knockout reactions.