MINOS+
Coordinates: 47°49′12″N 92°14′30″W / 47.82000°N 92.24167°W MINOS+ is a continuation of the MINOS detectors with improved electronics.[1] It will start taking data in 2013 and run for 3 years.
Physics Goals [1]
- Measure sin22θ and Δm2 with higher precision.
- Measure sin22θbar and Δmbar2 with higher precision.
- Study high energy neutrinos
- Search for sterile neutrinos
- Search for Tau neutrinos
- Non-Standard Interactions
- Measurement of the neutrino time of flight
- Search for extra dimensions
- Atmospheric neutrinos
Neutrino Beam
To produce the 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. Most of these are muon neutrinos, with a small electron neutrino contamination. Neutrino interactions in the near detector are used to measure the initial neutrino flux and energy spectrum. Because they are weakly interacting and therefore usually pass through matter, the vast majority of the neutrinos travel through the near detector and the 734 km of rock, then through the far detector and off into space. For the initial 3-year run the NuMI beam will be in its medium energy configuration which will deliver the majority of neutrinos with an energy between 4 GeV and 10 GeV.
Relationship with NOvA
NOvA sits 14 milliradians off the central line of the NuMI beam. This is so there is an enhancement of neutrinos with an energy of 2 GeV, which is the energy that the muon neutrinos have maximum oscillation. This causes a problem in that the signal you are looking for is a dip in a peak. MINOS+ sits on the central line of the beam so the full beam make up is seen, thus helping control systematic errors for the NuMI beam energy.
References
- 1 2 Tzanankos, G; et al. (2011). "MINOS+: a Proposal to FNAL to run MINOS with the medium energy NuMI beam" (PDF). FERMILAB-PROPOSAL-1016.
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