LHCb Scintillating Fibre Tracker Engineering Design Review Report: Fibres, Mats and Modules

During the Long Shutdown 2 of the LHC, the LHCb collaboration will replace the current Outer and Inner Tracker by a single tracking detector, based on 2.42m long scintillating fibres with a diameter of 250 $\mu$m, readout by silicon photo-multipliers (SiPM). The fibers are arranged in mats of 6 fibre-layers with a width of 130.65 mm. Eight fibre mats will form a module and are sandwiched between honeycomb and carbon fibre composite panels to provide stability and support over the module length of 4.85m. At either end of the module are the interfaces to the SiPMs and the front-end electronics. The active detection area of the Scintillating Fiber Tracker (SciFi) of 360m$^2$ will comprise 144 single modules arranged in 12 detection planes. This document summarizes the engineering design of the fibre mats and of the modules including the interfaces to the SiPMs and the mounting to the detector frames. Mechanical and detector properties of several prototype modules are discussed. The production procedure of the fibre-mats and the modules is introduced and time and cost estimates are given. Details of the mounting of the SiPM inside a cold-box as well as the connection to the front-end electronics is subject of a separate EDR. Detector frames are also excluded from the discussion in this document