Humboldt-Universität zu Berlin - Mathematisch-Naturwissen­schaft­liche Fakultät - Experimentelle Elementarteilchenphysik

The Search for Hidden Particles(=SHiP) experiment proposal at a dedicated proton beam-dump facility at the CERN SPS aims to search for feebly interacting particles (such as right-handed Majorana neutrinos, axion-like particles, dark photons, dark scalars) in the mass range ot a few 100 MeV up to a few GeV. Such particles are predicted in many extensions of the standard model to address open puzzles in elementary particle physics such as existence and smallness of neutrino masses, matter-antimatter asymmetry of the universe, and dark matter. The principle of the experiment is as follows: 400 GeV protons are dumped in a long heavy-metal target. Hadrons are absorbed in an absorber and the produced charged muons are either stopped or deflected by a magnetized muon shield. Feebly interacting particles such as right-handed Majorana neutrinos that are produced in the proton-nuclei collisions are expected to have long lifetimes and can decay in a subsequent 50 m long decay volume. They are reconstructed in a subsequent detector.