From obstacle to opportunity: uncovering the silver lining of pileup
arXiv:2503.11760 · doi:10.1016/j.physletb.2025.140121
Abstract
The lack of evidence for Beyond Standard Model (BSM) particles might be due to their light mass and very weak interactions, as exemplified by BSM long-lived particles (LLPs). Such particles can be produced from or hadron decays. Typically, the high values of pileup (PU) in hadron colliders are expected to pose a major challenge in light new physics searches. We propose a fresh perspective that counters this conventional wisdom: instead of viewing PU solely as an impediment, we highlight its potential benefits in searches for light LLPs from or hadron decays at HL-LHC and FCC-hh. In particular, certain forward detectors in LHC experiments, such as the Zero Degree Calorimeters (ZDC), which are currently not utilized for LLP searches, can be repurposed with strategic modifications to play a crucial role in this endeavor. Leveraging a combination of forward and central detectors, along with smart strategies for triggering and offline analysis, we demonstrate the potential for exploring light LLPs in high PU scenarios.
10 pages, 9 figures, 2 tables