The digitisation of the scintillating fibre detector

In this note the digitisation of the scintillating fibre detector for the LHCb upgrade is described. The steps for transforming the hits generated by the GEANT simulation into a digital signal are given. The main effects of this detector are described in the simulation code for the LHCb upgrade. In particular, the attenuation of the fibres after irradiation, the geometry of the fibres with respect to the SiPM channels, the gain of the SiPM’s, the thermal noise, the noise from afterpulses and spillover, and the clustering are described. The output is given in the same data format as the one that is expected from the final detector.