An OPERA for neutrinos
© J.-L. Caron/CERN
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Diagram showing the path of the neutrino beam from CERN all the way to the Laboratory of Gran Sasso in Italy.
The OPERA1 facility was inaugurated at the Gran Sasso National Laboratory2 on
September 11th 2006. Hopes are that it will prove that neutrinos can undergo transformation during their lifespan. Neutrinos, which are produced inside stars, are the most abundant elementary particles of matter in the Universe, but also the smallest and the most “invisible,” since they have no charge and can only be detected via their interactions. From October onwards, the European Organization for Nuclear Research (CERN) will send a beam of billions of muon neutrinos through the Earth's crust towards the underground laboratory in Italy, located 730 km away. When they get there, they will strike a succession of 31 walls made up of sophisticated target “bricks” containing lead. When they impact the lead, any muon neutrinos that have turned into tau neutrinos will emit a tau particle that will be detected by a photographic gel. The experiment, set to last 5 years, mainly involves Japanese and European laboratories, of which four are at CNRS' IN2P3.3
1. Oscillation Project with Emulsion-tRacking Apparatus.
2. The largest underground facility in the world for experimental particle physics research, located near Rome.
3.Institut National de Physique Nucléaire et de Physique des Particules (National Institute of Nuclear and Particle Physics).