Design of a Si-CsI detector for cluster measurements in the large-acceptance multipurpose spectrometer at RAON

We have designed a Si-CsI detector for measuring clusters from nuclear collisions in the forward region of the large-acceptance multipurpose spectrometer at RAON. The detector consists of two inclined annular rings, and covers the pseudorapidity from 1. 6 to 2. 1. Each ring comprises eight modules, and each module has three silicon layers and one CsI crystal bar. A realistic simulation demonstrates that the current design can identify isotopes at least up to Z = 9. The maximum measurable kinetic-energy range is distributed from 100 MeV to 1 GeV depending on the mass and Z. The Si-CsI detector will be useful for the study of the nuclear symmetry energy at RAON.