Looking for milli-charged particles with a new experiment at the LHC

Abstract We propose a new experiment at the Large Hadron Collider (LHC) that offers a powerful and model-independent probe for milli-charged particles. This experiment could be sensitive to charges in the range 10 − 3 e – 10 − 1 e for masses in the range 0.1–100 GeV, which is the least constrained part of the parameter space for milli-charged particles. This is a new window of opportunity for exploring physics beyond the Standard Model at the LHC. The key new ingredients of the proposal are the identification of an optimal location for the detector and a telescopic/coincidence design that greatly reduces the background.