Search for Emerging Jets in the CMS Detector

Dark matter could be explained by a hidden sector in which particles exist with a minimal connection to the known universe. We can probe some of these models by searching for their Standard Model decay products in the CMS detector at the Large Hadron Collider. In this search, we investigate a hidden dark sector analogous to Quantum Chromodynamics, where dark quarks hadronize into dark pions, which then decay back into standard model quarks forming a unique jet structure that would be accessible to look for in the detector. All interactions between the standard model and the dark sector are determined by a mediator particle. Using proton-proton collisions at an energy of around 13 TeV, we search for events in which a pair of mediator particles are produced, each of which decays into one dark quark and one standard model quark, resulting in a total of two normal jets and two emerging jets. The most recent analysis includes scenarios with flavor-aligned and down-type coupling scenarios for the dark sector, yielding new exclusion limits on mediator masses and setting further limits on potential dark sector scenarios. Going forward, the study will extend to up-type coupling scenarios involving top quark production, which could provide novel signatures due to the top quark's large mass and unique decay properties. This ongoing search offers promising prospects for probing dark matter candidates through unique jet structures, and will likely continue to develop.