There are two dedicated searches for the SUSY Electroweak production performed at ATLAS-CPPM. The first one is a search for the direct production of chargino and neutralino, where the neutralino decays into a Z boson and the lightest SUSY particle, and the chargino into a W boson and the LSP. The second search is for the chargino pair production, where each chargino decays into W boson and the LSP. In both searches, we focus on the scenario where the W boson decays leptonically while the other W or Z boson decays hadronically. The final states are therefore characterized by the presence of one isolated lepton, jets and missing transverse momentum. The two analyses via this one-lepton channel are conducted for the first time at LHC and target an integrated luminosity of 139 fb-1 corresponding to the full ATLAS Run-2 (2015-2018) collected data.
The High Luminosity Large Hadron Collider (HL-LHC) is an upgrade to the LHC, that will be operational in 2027 and aim to increase the luminosity by a factor of 10 in order to allow better studies of known mechanisms and boost the potential for new discoveries as well. The B-Layer and IBL, which were installed during LHC Run-1 and Run-2 and designed to work effectively with a fluence up to 10^15 and 2×10^15 1-MeV neutrons per cm2, respectively, will suffer during Run-3 and not be able to withstand the HL-LHC radiation levels. Consequently, they will be replaced by a new full silicon tracker (ITK) in the LHC LS3 (2025- 2026) for the HL-LHC. The innermost layer of ITK can withstand up to 10^16 n(1 MeV)/cm2 which is only a half of the total dose foreseen for the entire lifetime of HL-LHC, thereby leading to a replacement for ITK by the HL-LHC half-life. One of the potential candidates for ITK replacement is the CMOS technology which has shown up many advantages in the electronic industry for 20 years. With smaller pixel size and monolithic design, CMOS sensors will provide a better spatial resolution and a reduction of the detector cost as well. Our group is contributing to the R&D effort to make CMOS sensors radiation- hard enough for the HL-LHC and also investigating what can be gained from the ITK replacement.