User Manual for the Allpix$^2$ Simulation Framework

Several simulation tools exist for the detailed study of position sensitive silicon detectors, covering aspects ranging from the electrical properties of sensors to the behaviour of charged particles traversing a given detector setup. Each of these toolkits performs a very specialised task, and for the complete description of a silicon detector several such software packages must typically be used. Allpix$^2$ builds upon this work by providing a complete and easy-to-use C++ software package for simulating detector performance, from the interaction of particles to the digitisation of propagated carriers by the front-end electronics. A modular framework is used to flexibly add or remove modules from the simulation chain, each performing specific tasks such as interfacing to Geant4 to deposit energy in the detector and provide an accurate description of material effects, or the propagation of deposited charges through the sensor bulk. This document presents the user manual of the software as of release version 1.0.2.