Minos

MINOS (or Main Injector Neutrino Oscillation Search) is an experiment at Fermilab, designed to study the phenomena of neutrino oscillations.

Related Topics:
Experiment - Fermilab - Neutrino oscillation

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Neutrinos produced by the NuMI (or "Neutrinos at Main Injector") beamline are observed at the Near and Far detectors, placed 735km apart. The Far detector has a mass of 5.4 ktons. It is located in the Soudan mine in Northern Minnesota at a depth of 716 meters. The Far detector has been fully operational since summer 2003, and has been taking atmospheric muon and neutrino data since early in its construction. The Near detector is similar to the Far detector in design, but smaller in size with a mass of 980 tons. It is located at Fermi National Accelerator Laboratory (FNAL), a few hundreds meters away from the target, and approximately 100 meters underground. The commissioning of the Near detector was completed in December 2004, and it is now fully operational. The MINOS experiment has started detecting neutrinos from the NuMI beam in February, 2005.

Related Topics:
Neutrino - NuMI - Ktons - Soudan mine - Minnesota - 2003 - Muon - Ton - 2004 - 2005

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In NuMI beamline 120 GeV Main Injector proton pulses hit a water-cooled graphite target. The resulting interactions of protons with the target material produce pions and kaons, which are focused by a system of magnetic horns. The neutrinos from subsequent decays of pions and kaons form the neutrino beam. Neutrino interactions in the Near detector are used to measure the initial muon-neutrino flux and energy distribution. The vast majority of the neutrinos travel through the Near detector and Earth matter without interacting. On the way toward Soudan, a fraction of muon-neutrinos oscillate into other flavors. MINOS will measure the difference in neutrino beam composition and energy distribution in the Near and Far detectors. This will allow precision measurements of the neutrino-mass difference and oscillation angle. In addition, MINOS will look for the appearance of electron neutrinos in the Far detector, and would either measure or set a limit on the oscillation probability of muon-neutrinos into electron-neutrinos. Both of the MINOS detectors are steel-scintillator sampling calorimeters made out of alternating planes of magnetized steel and plastic scintillator. The magnetic field makes it possible to separate neutrino and anti-neutrino interactions. This unique feature of the MINOS detectors allows MINOS to search for CP violation with atmospheric neutrinos and anti-neutrinos.

Related Topics:
Proton - Graphite - Pion - Kaon - Magnet - Neutrino beam - Flux - Flavor - Oscillation - Electron neutrino - Steel - Scintillator - Calorimeter - Plastic - Anti-neutrino - CP

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