| Beyond the Standard Model |
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| Standard Model |
Laboratori Nazionali del Gran Sasso (LNGS) is a particle physics laboratory of the INFN, situated near the Gran Sasso mountain in Italy, between the towns of L'Aquila and Teramo, about 120 km from Rome. In addition to a surface portion of the laboratory, there are extensive underground facilities beneath the mountain. The first large experiments at LNGS ran in 1989; the facilities were later expanded. According to its official website, the Gran Sasso lab is, as of 2006[update], the largest underground particle physics laboratory in the world.
The lab is located within the Gran Sasso and the Monti della Laga National Park. The underground facilities are located next to a freeway tunnel, the 10 km long Traforo del Gran Sasso. The experimental halls are covered by about 1400m of rock, protecting the experiments from cosmic rays.
The mission of the laboratory is to host experiments that require a low background environment in the field of astroparticle physics and nuclear astrophysics and other disciplines that can profit of its characteristics and of its infrastructures. The LNGS is, like the three other European underground astroparticle laboratories, Laboratoire Souterrain de Modane, Laboratorio subterráneo de Canfranc, and Boulby Underground Laboratory, a member of the coordinating group ILIAS.
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Since late August 2006, CERN has directed a beam of muon neutrinos from the CERN SPS accelerator to the Gran Sasso lab, 730 km away, where they will be detected by the OPERA and ICARUS detectors, in a study of neutrino oscillations that will improve on the results of the Fermilab to MINOS experiment.
In May 2010, Lucia Votano, Director of the Gran Sasso laboratories, announced that "[t]he OPERA experiment has reached its first goal: the detection of a tau neutrino obtained from the transformation of a muon neutrino, which occurred during the journey from Geneva to the Gran Sasso Laboratory."[1] This finding indicates a deficiency in the Standard Model of particle physics, as neutrinos would have to have mass for this change to occur.
An effort to determine the mass of the neutrino, called CUORE (Cryogenic Underground Observatory for Rare Events), is scheduled to begin in 2011. The detector will be shielded with lead recovered from an ancient Roman shipwreck, due to the ancient lead's lower radioactivity than recently minted lead. The artifacts are being given to CUORE from the National Archaeological Museum in Cagliari.[2]
In September 2011, Dario Autiero of the OPERA collaboration presented findings that indicated neutrinos were arriving at OPERA about 60 ns earlier than they would if they were travelling at the speed of light. This OPERA neutrino anomaly is as yet unexplained.[3][4]
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