This paper describes the hardware and operations of the Neutrinos at the Main Injector (NuMI) beam at Fermilab. It elaborates on the design considerations for the beam as a whole and for individual elements. The most important design details of indiv
idual components are described. Beam monitoring systems and procedures, including the tuning and alignment of the beam and NuMI long-term performance, are also discussed.
We report a two-detector measurement of the propagation speed of neutrinos over a baseline of 734 km. The measurement was made with the NuMI beam at Fermilab between the near and far MINOS detectors. The fractional difference between the neutrino spe
ed and the speed of light is determined to be $(v/c-1) = (1.0 pm 1.1) times 10^{-6}$, consistent with relativistic neutrinos.
We report the first observation of seasonal modulations in the rates of cosmic ray multiple-muon events at two underground sites, the MINOS Near Detector with an overburden of 225 mwe, and the MINOS Far Detector site at 2100 mwe. At the deeper site,
multiple-muon events with muons separated by more than 8 m exhibit a seasonal rate that peaks during the summer, similar to that of single-muon events. In contrast and unexpectedly, the rate of multiple-muon events with muons separated by less than 5-8 m, and the rate of multiple-muon events in the smaller, shallower Near Detector, exhibit a seasonal rate modulation that peaks in the winter.
Kinematic distributions from an inclusive sample of 1.41 x 10^6 charged-current nu_mu interactions on iron, obtained using the MINOS Near Detector exposed to a wide-band beam with peak flux at 3 GeV, are compared to a conventional treatment of neutri
no scattering within a Fermi gas nucleus. Results are used to guide the selection of a subsample enriched in quasielastic nu_mu Fe interactions, containing an estimated 123,000 quasielastic events of incident energies 1 < E_nu < 8 GeV, with <E_nu> = 2.79 GeV. Four additional subsamples representing topological and kinematic sideband regions to quasielastic scattering are also selected for the purpose of evaluating backgrounds. Comparisons using subsample distributions in four-momentum transfer Q^2 show the Monte Carlo model to be inadequate at low Q^2. Its shortcomings are remedied via inclusion of a Q^2-dependent suppression function for baryon resonance production, developed from the data. A chi-square fit of the resulting Monte Carlo simulation to the shape of the Q^2 distribution for the quasielastic-enriched sample is carried out with the axial-vector mass M_A of the dipole axial-vector form factor of the neutron as a free parameter. The effective M_A which best describes the data is 1.23 +0.13/-0.09 (fit) +0.12/-0.15 (syst.) GeV.
The MINOS experiment uses a beam of predominantly muon-type neutrinos generated using protons from the Main Injector at Fermilab in Batavia, IL, and travelling 735 km through the Earth to a disused iron mine in Soudan, MN. The 10{mu}s-long beam pulse
contains fine time structure which allows a precise measurement of the neutrino time of flight to be made. The time structure of the parent proton pulse is measured in the beamline after extraction from the Main Injector, and neutrino interactions are timestamped at the Fermilab site in the Near Detector (ND), and at the Soudan site in the Far Detector (FD). Small, transportable auxiliary detectors, consisting of scintillator planes and associated readout electronics, are used to measure the relative latency between the two large detectors. Time at each location is measured with respect to HP5071A Cesium clocks, and time is transferred using GPS Precise Point Positioning (PPP) solutions for the clock offset at each location. We describe the timing calibration of the detectors and derive a measurement of the neutrino velocity, based on data from March and April 2012. We discuss the prospects for further improvements that would yield a still more accurate result.
A sample of 1.53$times$10$^{9}$ cosmic-ray-induced single muon events has been recorded at 225 meters-water-equivalent using the MINOS Near Detector. The underground muon rate is observed to be highly correlated with the effective atmospheric tempera
ture. The coefficient $alpha_{T}$, relating the change in the muon rate to the change in the vertical effective temperature, is determined to be 0.428$pm$0.003(stat.)$pm$0.059(syst.). An alternative description is provided by the weighted effective temperature, introduced to account for the differences in the temperature profile and muon flux as a function of zenith angle. Using the latter estimation of temperature, the coefficient is determined to be 0.352$pm$0.003(stat.)$pm$0.046(syst.).
We report on a new analysis of neutrino oscillations in MINOS using the complete set of accelerator and atmospheric data. The analysis combines the $ u_{mu}$ disappearance and $ u_{e}$ appearance data using the three-flavor formalism. We measure $|De
lta m^{2}_{32}|=[2.28-2.46]times10^{-3}mbox{,eV}^{2}$ (68% C.L.) and $sin^{2}theta_{23}=0.35-0.65$ (90% C.L.) in the normal hierarchy, and $|Delta m^{2}_{32}|=[2.32-2.53]times10^{-3}mbox{,eV}^{2}$ (68% C.L.) and $sin^{2}theta_{23}=0.34-0.67$ (90% C.L.) in the inverted hierarchy. The data also constrain $delta_{CP}$, the $theta_{23}$ octant degeneracy and the mass hierarchy; we disfavor 36% (11%) of this three-parameter space at 68% (90%) C.L.
In the RADAR project described in this Letter of Intent, we propose to deploy a 6 kton liquid argon TPC at the NOvA Far Detector building in Ash River, Minnesota, and expose it to the NuMI beam during NOvA running. It will significantly add to the ph
ysics capabilities of the NOvA program while providing LBNE with an R&D program based on full-scale TPC module assemblies. RADAR offers an excellent opportunity to improve the full Homestake LBNE project in physics reach, timeline, costs, and fostering international partnership. The anticipated duration of the projects construction is 5 years, with running happening between 2018 and 2023.
This Letter of Intent outlines a proposal to build a large, yet cost-effective, 100 kton fiducial mass water Cherenkov detector that will initially run in the NuMI beam line. The CHIPS detector (CHerenkov detector In Mine PitS) will be deployed in a
flooded mine pit, removing the necessity and expense of a substantial external structure capable of supporting a large detector mass. There are a number of mine pits in northern Minnesota along the NuMI beam that could be used to deploy such a detector. In particular, the Wentworth Pit 2W is at the ideal off-axis angle to contribute to the measurement of the CP violating phase. The detector is designed so that it can be moved to a mine pit in the LBNE beam line once that becomes operational.
We report measurements of oscillation parameters from $ u_{mu}$ and $bar{ u}_{mu}$ disappearance using beam and atmospheric data from MINOS. The data comprise exposures of unit[$10.71 times 10^{20}$]{protons on target (POT)} in the $ u_{mu}$-dominate
d beam, $unit[3.36times10^{20}]{POT}}$ in the $bar{ u}_{mu}$-enhanced beam, and 37.88 kton-years of atmospheric neutrinos. Assuming identical $ u$ and $bar{ u}$ oscillation parameters, we measure mbox{$|Delta m^2}| = unit[2.41^{+0.09}_{-0.10}) times 10^{-3}]{eV^{2}}$} and $sin^{2}/!/left(2theta right) = 0.950^{+0.035}_{-0.036}$. Allowing independent $ u$ and $bar{ u}$ oscillations, we measure antineutrino parameters of $|Delta bar{m}^2| = unit[(2.50 ^{+0.23}_{-0.25}) times 10^{-3}]{eV^{2}}$ and $sin^{2}/!/left(2bar{theta} right) = 0.97^{+0.03}_{-0.08}$, with minimal change to the neutrino parameters.
