Abstract
Many existing or proposed intensity-frontier search experiments look for decay signatures of light long-lived particles (LLPs), highly displaced from the interaction point, in a distant detector that is well-shielded from SM background. This approach is, however, limited to new particles with decay lengths similar to or larger than the baseline of those experiments. In this study, we discuss how this basic constraint can be overcome in BSM models that go beyond the simplest scenarios. If more than one light new particle is present in the model, an additional secondary production of LLPs may take place right in front of the detector, opening this way a new lifetime regime to be probed. We illustrate the prospects of such searches in the future experiments FASER, MATHUSLA and SHiP, for representative models, emphasizing possible connections to dark matter or an anomalous magnetic moment of muon. We also analyze additional advantages from employing dedicated neutrino detectors placed in front of the main decay volume.
Highlights
Motivated by a successful history of discoveries of new elementary particles, it has long been the dominant paradigm in experimental searches to look for heavier and heavier particles that could manifest their existence in increasingly more powerful colliders
In order to illustrate the interplay between the primary and secondary production mechanisms, we have studied the sensitivity reach for selected long-lived particles (LLPs) models in the FASER, MATHUSLA, and SHiP experiments
These potentially very clean searches are limited by the lifetime of LLPs that need to travel the entire distance to the detector
Summary
Motivated by a successful history of discoveries of new elementary particles, it has long been the dominant paradigm in experimental searches to look for heavier and heavier particles that could manifest their existence in increasingly more powerful colliders. This approach led to a well-established experimental program that is being continued at the Large Hadron Collider (LHC). The corresponding efforts are often referred to as intensity frontier searches for light long-lived particles (LLPs) This captures the fact that the relevant detection prospects depend upon the ability to study very rare events that should be discriminated from a priori overwhelming Standard Model (SM) background (BG)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
