2016/01/31 by Jared A. Evans, Jessie Shelton · 4 citations
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #Dark Matter and Cosmic Phenomena #Dark matter #Large Hadron Collider #Lepton #Minimal Supersymmetric Standard Model #Naturalness #Parameter space #Particle physics theoretical and experimental studies #Physics beyond the Standard Model #hep-ph
paper · pdf · doi:10.1007/jhep04(2016)056
published as JHEP 1604 (2016) 056 · 48 pages, 6 figures, journal version
openalex publication_date 2016/04/01 · arxiv created 2016/04/14 · arxiv updated 2016/05/04 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
As the majority of LHC searches are focused on prompt signatures, specific long-lived particles have the potential to be overlooked by the otherwise systematic new physics programs at ATLAS and CMS. While in many cases long-lived superparticles are now stringently constrained by existing exotic searches, we point out that the highly motivated model of gauge mediation with staus as the next-to-lightest superparticle (NLSP) is relatively far less tested. We recast LHC searches for heavy stable charged particles, disappearing tracks, and opposite-flavor leptons with large impact parameters to assess current constraints on a variety of spectra that contain an NLSP stau, and find that portions of the parameter space motivated by naturalness are still experimentally unexplored. We additionally note a gap in the current experimental search program: same-flavor leptons with large impact parameters evade the suite of existing searches for long-lived objects. This gap is especially noteworthy as vetoes on displaced leptons in prompt new physics searches could be systematically discarding such events. We discuss several motivated models that can exhibit same-flavor displaced leptons: gauge mediation with co-NLSP sleptons, extended gauge mediation, R-parity violation, and lepton-flavored dark matter that freezes in during a matter-dominated era of the early universe. To address this gap, we propose a straightforward extension of the CMS search for leptons with large impact parameters, and project sensitivity to these scenarios at 13 TeV. Throughout this analysis, we highlight several methods whereby LHC searches for exotic long-lived objects could potentially improve their sensitivity to the displaced leptons originating from gauge mediation and beyond.