Abstract
The most recent CMS results from a search for supersymmetry (SUSY) with a compressed mass spectrum in leptonic final states will be presented. The search is targeting signatures with missing transverse momentum and two or three low-momentum (soft) leptons. The dataset used is collected by the CMS experiment during the Run–2 proton-proton collisions at TeV at the LHC, and corresponds to an integrated luminosity of up to 137 fb−1. The observed data are found to be in agreement with the Standard Model prediction and exclusion upper limits are set on the SUSY particles production cross section. The results are interpreted in terms of electroweakino and top squark pair production. In both cases, a small mass difference between the produced SUSY particles and the lightest neutralino is considered. A wino-bino and a higgsino simplified models are used for the electroweakino interpretation. Exclusion limits at 95% confidence level are set on masses up to 280 GeV for a mass difference between the and the lightest neutralino of 10 GeV for the wino-bino production. In the higgsino interpretation masses are excluded up to 210 GeV for a mass difference of 7.5 GeV and up to 150 GeV for a mass difference of 3 GeV. The results for the higgsino production are additionally interpreted in terms of a phenomenological minimal SUSY extension of the standard model, excluding the higgsino mass parameter μ up to 180 GeV for bino mass parameter M1 = 800 GeV. Upper limits at 95% confidence level are set on the top squark pair production interpretation, excluding top squark masses up to 530 GeV in the four-body top squark decay model and up to 475 GeV in the chargino-mediated decay model for a mass difference between the top squark and the lightest neutralino of 30 GeV.
Highlights
Introduction and MotivationDespite its great success in describing known phenomena and predicting new ones, the standard model (SM) of particle physics has left a number of fundamental questions unanswered
The uncertainties related to the experiment and to the modelling of the signal and the background processes are included in the fit as nuisance parameters
The search is conducted with the full Run–2 dataset that corresponds to an integrated luminosity of up to 137 fb−1
Summary
Introduction and MotivationDespite its great success in describing known phenomena and predicting new ones, the standard model (SM) of particle physics has left a number of fundamental questions unanswered. Apart from the two χ01, which contribute to the pmTiss of the event, a requirement for the leptonic decay of the Z boson leads to a final state with two same flavor (SF) and opposite sign charge (OS) that largely reduces background contributions from QCD processes. The minimum M ( ), MSmFiOn S( ), of the two possible SFOS lepton pairs is used for 3 EWK SRs. The maximum M ( ) of the lepton pair combinations is required to be less than 60 GeV to veto SM events with an on-shell Z boson.
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
