Scintillating Ring Detector

The Scintillating Ring detector (SciRi) covers the acceptance gap between the BGO Ball and the rectangular forward spectrometer. It also partly overlaps with the scintillator barrel and MWPCs. SciRi is a segmented plastic scintillator detector used for reconstruction of charged particles direction. It is made of 96 elements of 20mm thickness, arranged in three rings. Each ring covers ∆θ = 5°, the whole detector covers the polar angular range of θ = (10 ÷ 25)°. In φ one element covers ∆φ = 11.5°, which is the same as for the BGO Ball. The whole detector is mounted inside the forward opening cone of the BGO.

The scintillator elements are individually read out by Hamamatsu S11048(X3) avalanche photo diodes (APDs). A time resolutions of approximately 3ns can be achieved.