Simulation of Luminosity Monitoring in ATLAS

A fast and flexible simulation program has been written and used to study different aspects related to the luminosity monitoring in ATLAS. This was made both in order to answer questions related to the planned luminosity monitor LUCID and to study the possibility of using the beam condition monitor and the minimum bias trigger scintillator counters as additional luminosity monitors. The study was made using {\tt Pythia v6.319} events at generator level and a simple program simulating the detector response of the luminosity monitors. Studies related to particle rates and the acceptance of inelastic events were made with respect to the different luminosity monitors and the saturation effect due to an imperfect particle counting was estimated. A detailed study of luminosity monitoring using bunch crossings which are registered in both the A and C side detector modules was made where the effects were both estimated by the simulation and explained by Poisson statistics.