Search for new physics in the compressed mass spectra scenario in events with three soft light leptons at 13 TeV with the CMS experiment

The analysis strategy to search for signs of “electroweakinos” in a compressed SUSY mass spectrum with soft three leptons, electrons or muons, in the final state is presented. The analysis is conceived for the 13 TeV pp collisions the CMS experiment has collected in the first six months of 2016. In particular we concentrated on the scenario where the lightest chargino () and the second-lightest neutralino () are pair produced and degenerate in mass, and decay to the lightest neutralino (LSP) and a virtual W and Z boson, respectively. The bosons decay leptonically. The typical difference in mass considered between the LSP and the chargino is of 20 GeV.