Aachen 2019 – scientific programme
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T: Fachverband Teilchenphysik
T 81: Supersymmetrie II
T 81.10: Talk
Thursday, March 28, 2019, 18:15–18:30, S07
Search for disappearing tracks with the CMS experiment at √s=13 TeV — •Viktor Kutzner1, Samuel Bein1, Seh Wok Lee3, Isabell Melzer-Pellmann2, Sang-Il Pak3, Alexandra Tews1, Peter Schleper1, Sezen Sekmen3, Akshansh Singh2, Jory Sonneveld1, Georg Steinbrück1, and Benedikt Vormwald1 — 1Institut für Experimentalphysik, Universität Hamburg — 2DESY — 3Kyungpook National University
Long-lived charginos are predicted in theories with a small mass splitting between the two lightest particles, such as anomaly-mediated supersymmetry breaking (AMSB). Here, the two lightest particles are typically a chargino and a neutralino. Given a sufficiently small mass splitting in the range of mπ Δ m 200 MeV, the chargino is expected to decay in the CMS tracker volume into soft non-reconstructed leptons or hadrons and a lightest supersymmetric particle, leaving a disappearing track. This signature is characterized by missing hits in the outer layers of the tracker with little or no energy deposited in the calorimeter. The search includes short disappearing tracks with only a few hits in the tracking detector, as well as events with several jets and disappearing tracks. Events with b-quark jets are investigated as well to account for gluino-/squark-associated chargino production. Disappearing tracks are identified using a boosted decision tree, and data-driven methods are used to determine the dominant backgrounds arising from prompt leptons and fake tracks. Results are presented using proton-proton collision data with √s=13 TeV collected with the CMS experiment during Run-2.