Deriving New LHC Constraints on Displaced Superparticles

by Brock Tweedie (Boston University)

Tuesday 9 Dec 2014, 15:00 → 16:00 US/Central

WH11NE (Sunrise Room) (Fermilab)

Supersymmetry searches at the LHC are both highly varied and highly constraining, but the vast majority are focused on cases where the final-stage visible decays are prompt. Scenarios with superparticles that have detector-scale lifetimes have therefore remained a tantalizing possibility, in which explicit limits are relatively sparse. Nonetheless, the extremely low backgrounds of the few existing searches for metastable and displaced new particles facilitates recastings into powerful long-lived superparticle searches, even for models for which those searches are highly non-optimized. We assess the status of several such models in the context of baryonic R-parity violation, gauge mediation, and mini-split SUSY. We focus on simplified spectra where fully hadronic final-stage decays can be important. Possibilities considered include generic colored superparticles such as gluinos and light-flavor squarks, as well as the lighter stop and the quasi-degenerate Higgsino multiplet motivated by naturalness. Complementary coverage over large swaths of mass and lifetime is achievable by combining limits, particularly from the CMS displaced dijet search and heavy stable charged particle searches. Adding in prompt searches, we find many cases where a range of sparticle masses is now excluded from zero lifetime to infinite lifetime, with no gaps.