Çetin, Serkant Ali2020-11-042020-11-042020-10-011029-8479https://hdl.handle.net/11411/2431https://doi.org/10.1007/JHEP10(2020)00546 pagesA search for a chargino-neutralino pair decaying via the 125 GeV Higgs boson into photons is presented. The study is based on the data collected between 2015 and 2018 with the ATLAS detector at the LHC, corresponding to an integrated luminosity of 139 fb(-1) of pp collisions at a centre-of-mass energy of 13 TeV. No significant excess over the expected background is observed. Upper limits at 95% confidence level for a massless (chi) over tilde (0)(1) are set on several electroweakino production cross-sections and the visible cross-section for beyond the Standard Model processes. In the context of simplified supersymmetric models, 95% confidence-level limits of up to 310 GeV in m((chi) over tilde (+/-)(1)/(chi) over tilde (0)(2)), where m((chi) over tilde (0)(1)) = 0.5 GeV, are set. Limits at 95% confidence level are also set on the (chi) over tilde (+/-)(1)(chi) over tilde (0)(2) cross-section in the mass plane of m((chi) over tilde (+/-)(1)/(chi) over tilde (0)(2)) and m((chi) over tilde (0)(1)), and on scenarios with gravitino as the lightest supersymmetric particle. Upper limits at the 95% confidence-level are set on the higgsino production cross-section. Higgsino masses below 380 GeV are excluded for the case of the higgsino fully decaying into a Higgs boson and a gravitino.1 Introduction 1 2 ATLAS detector 3 3 Data and simulation samples 4 4 Event reconstruction 6 5 Event selection 9 5.1 Baseline selection 9 5.2 Follow-up selection 10 6 Signal and background parameterisation 10 7 Systematic uncertainties 11 8 Results 14 8.1 Limits on the visible cross-section 15 8.2 Interpretation of the wino-like model 16 8.3 Interpretation of the higgsino-like h ~ Gh~G model 17 9 Conclusion 18 The ATLAS collaborationeninfo:eu-repo/semantics/openAccessHadron-Hadron scattering (experiments)Article2-s2.0-8509195382710.1007/JHEP10(2020)005Q1WOS:000576978000001