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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 speed and the speed of light is determined to be (v/c-1) = (1.0 ± 1.1) x 10-6, consistent with relativistic neutrinos. [ABSTRACT FROM AUTHOR]

Evidence of a heavy neutrino, νH, in the K+ → µ+ νH decays was sought using the E949 experimental data with an exposure of 1.70 × 1012 stopped kaons. With the major background from the radiative K+ → µ+νµγ decay understood and suppressed, upper limits (90% C.L.) on the neutrino mixing matrix element between the muon and heavy neutrinos, |UµH|², were set at the level of 10-7 to 10-9 for the heavy neutrino mass region 175 to 300 MeV/c². [ABSTRACT FROM AUTHOR]

Kinematic distributions from an inclusive sample of 1.41×106 charged-current vμ 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 neutrino scattering within a Fermi gas nucleus. Results are used to guide the selection of a subsample enriched in quasielastic vμFe interactions, containing an estimated 123,000 quasielastic events of incident energies 1 < Ev < 8 GeV, with {Ev} = 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 Q² show the Monte Carlo model to be inadequate at low Q². Its shortcomings are remedied via inclusion of a Q²-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 Q² distribution for the quasielastic-enriched sample is carried out with the axial-vector mass MA of the dipole axial-vector form factor of the neutron as a free parameter. The effective MA which best describes the data is 1.23-0.09+0.13(fit)-0.15+0.12(syst) GeV. [ABSTRACT FROM AUTHOR]

A sample of 1.53 × 109 cosmic-ray-induced single muon events has been recorded at 225 m water equivalent using the MINOS near detector. The underground muon rate is observed to be highly correlated with the effective atmospheric temperature. The coefficient aT, relating the change in the muon rate to the change in the vertical effective temperature, is determined to be 0.428 ± 0.003(stat.) ± 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 ± 0.003(stat.) ± 0.046(syst.). [ABSTRACT FROM AUTHOR]

The CoGeNT Collaboration has recently published results from a fifteen month data set which indicate an annual modulation in the event rate similar to what is expected from weakly interacting massive particle interactions. It has been suggested that the CoGeNT modulation may actually be caused by other annually modulating phenomena, specifically the flux of atmospheric muons underground or the radon level in the laboratory. We have compared the phase of the CoGeNT data modulation to that of the concurrent atmospheric muon and radon data collected by the MINOS experiment which occupies an adjacent experimental hall in the Soudan Underground Laboratory. The results presented are obtained by performing a shape-free χ² data-to-data comparison and from a simultaneous fit of the MINOS and CoGeNT data to phase-shifted sinusoidal functions. Both tests indicate that the phase of the CoGeNT modulation is inconsistent with the phases of the MINOS muon and radon modulations at the 3.0s level. [ABSTRACT FROM AUTHOR]