Search for Long-Lived Particles Using Calorimeter Timing at the LHC

Long-lived particles (LLPs) are predicted in various theories beyond the Standard Model (SM). Given their non-standard nature, specialized techniques are needed for their detection. The LLPs, when produced at the LHC, travel a considerable distance before decaying into SM particles that are subsequently captured by a detector. However, when the LLPs are not boosted enough, they travel slowly and produce delayed particles. By measuring the timing of such decay products, one can test the existence of the LLPs. Calorimeter timing is an excellent tool for this, and we demonstrate that it brings improvement in sensitivity to a gauge-mediated SUSY breaking model. In particular, this work suggests that a dedicated trigger using calorimeter timing can provide a significant enhancement of sensitivity.