Dark sector searches in final states with prompt neutral particles with the ATLAS detector

Building a theory that can correctly describe the laws that govern the Universe at an infinitely small scale is the ultimate goal of Particle Physics. All knownfundamental particle interactions have been described so far by the Standard Model. This theory describes a system made up of fermions, or particles with a half-integerspin, known as quarks and leptons, and their interactions through the exchange of unitary-spin particles known as vector bosons, which mediates the strong, weak, and electromagnetic interactions.The Particle Physics community continues to put Standard Model predictions to test and, decade after decade, has discovered perfect agreement with experimental results.The last confirmation of the theory was given by ATLAS and CMS experiments at the LHC at CERN, with the announcement of the Higgs boson discovery in 2012,which represents the last success of the Standard Model.