The KATRIN Neutrino Experiment is an international collaboration of scientists and engineers working to measure the mass of the neutrino, one of the fundamental particles of the universe. The experiment is based at the Karlsruhe Institute of Technology in Germany and is the world
From Wikipedia
KATRIN is a German acronym for an undertaking to measure the mass of the electron antineutrino with sub-eV precision by examining the spectrum of electrons emitted from the beta decay of tritium. The experiment is a recognized CERN experiment (RE14). The core of the apparatus is a 200-ton spectrometer.