Assembly and installation of the Belle II TOP detector

The Time-of-Propagation (TOP) detector is a new type of ring-imaging Cherenkov detector developed for particle identification in the barrel region of the Belle II spectrometer. In the assembly and installation, it is crucial for the detector performance to achieve precision alignment and secure gluing of the optical components as well as to mechanically support them managing the stress, attitude, optical and electrical contacts, and limited installation space. Various efforts were made to develop the procedures and jigs along with the development of the mechanical structure. Such efforts accomplished the assembly and installation in April and May 2016, respectively, without a significant incident.