Protons from the Large Hadron Collider (LHC) can produce beam-induced backgrounds in the experimental areas through: (i) normal cleaning losses on tertiary collimators, (ii) elastic interactions with beam-gas over several orbits followed by losses on the tertiary collimators, and (iii) by inelastic beam-gas interactions up to 550 m from the centre of a given detector.
For a given set of collimator settings a set of loss maps are calculated by LHC physicists. These loss maps are then used to generate a series of proton-collimator collisions. The showers from these inelastic interactions are then carried through beam optics and shielding material to the experimental area interface plane. Both FLUKA [R. Bruce, V. Talanov] and MARS [N. Mokhov] have been used to transport showers to the experimental areas. SixTrack and MARS have also been used to simulate elastic beam-gas collisions over several orbits.
The Beam Background Generator is a simple program that reads text file particle records created from MARS or FLUKA simulations and converts them into HepMC format suitable for input into Geant4 simulations of LHC experiments. Input files can either be converted directly into HepMC format or used to generate showers of particles without correlations. The program can either read event records or weighted particle records.