Belle II Detector

The Belle II detector is an upcoming general-purpose spectrometer at the upgraded accelerator complex SuperKEKB at KEK in Tsukuba, Japan.

The Belle II detector consists of several sub-detector components:

• Two layers of pixelated silicon sensors (PXD) and four layers of double-sided silicon strip sensors (SVD) that measure decay vertex positions of B mesons and other particles,

• A central drift chamber (CDC) that measures trajectories, momenta and dE/dx information of charged particles,

• A barrel-shaped array of Time-Of-Propagation (TOP) counters that reconstruct, in spatial and time coordinates, the ring-image of Cherenkov light cones emitted from charged particles passing through quartz radiator bars, another ring-imaging Cherenkov counters with aerogel radiator in the forward end-cap (ARICH),

• An electromagnetic calorimeter (ECL) consisting of scintillator crystals located inside a superconducting solenoid coil that provides a 1.5 Tesla magnetic field, and

• An iron flux-return located outside of the coil which is instrumented to detect K0L mesons and to identify muons (KLM).