We measure neutrino charged current quasielastic-like scattering on hydrocarbon at high statistics using the wide-band NuMI beam with neutrino energy peaked at 6 GeV. The double-differential cross ...section is reported in terms of muon longitudinal and transverse momentum. Cross-section contours versus lepton momentum components are approximately described by a conventional generator-based simulation, however discrepancies are observed for transverse momenta above 0.5 GeV/c for longitudinal momentum ranges 3 to 5 GeV/c and 9 to 20 GeV/c. The single differential cross section versus momentum transfer squared (\(d\sigma/dQ_{QE}^2\)) is measured over a four-decade range of \(Q^2\) that extends to \(10~GeV^2\). The cross section turn-over and fall-off in the \(Q^2\) range 0.3 to \(10~GeV^2\) is not fully reproduced by generator predictions that rely on dipole form factors. Our measurement probes the axial-vector content of the hadronic current and complements the electromagnetic form factor data obtained using electron-nucleon elastic scattering. These results help oscillation experiments because they probe the importance of various correlations and final-state interaction effects within the nucleus, which have different effects on the visible energy in detectors.
The first direct measurement of electron neutrino quasielastic and quasielasticlike scattering on hydrocarbon in the few-GeV region of incident neutrino energy has been carried out using the MINERvA ...detector in the NuMI beam at Fermilab. The flux-integrated differential cross sections in the electron production angle, electron energy, and Q^{2} are presented. The ratio of the quasielastic, flux-integrated differential cross section in Q^{2} for ν_{e} with that of similarly selected ν_{μ}-induced events from the same exposure is used to probe assumptions that underpin conventional treatments of charged-current ν_{e} interactions used by long-baseline neutrino oscillation experiments. The data are found to be consistent with lepton universality and are well described by the predictions of the neutrino event generator GENIE.
We report new constraints on the size of large extra dimensions from data collected by the MINOS experiment between 2005 and 2012. Our analysis employs a model in which sterile neutrinos arise as ...Kaluza-Klein states in large extra dimensions and thus modify the neutrino oscillation probabilities due to mixing between active and sterile neutrino states. Using Fermilab’s Neutrinos at the Main Injector beam exposure of 10.56×1020 protons on target, we combine muon neutrino charged current and neutral current data sets from the Near and Far Detectors and observe no evidence for deviations from standard three-flavor neutrino oscillations. The ratios of reconstructed energy spectra in the two detectors constrain the size of large extra dimensions to be smaller than 0.45 μm at 90% C.L. in the limit of a vanishing lightest active neutrino mass. Stronger limits are obtained for nonvanishing masses.
Forward single π0 production by coherent neutral-current interactions, νA→νAπ0, is investigated using a 2.8×1020 protons-on-target exposure of the MINOS Near Detector. For single-shower topologies, ...the event distribution in production angle exhibits a clear excess above the estimated background at very forward angles for visible energy in the range 1–8 GeV. Cross sections are obtained for the detector medium comprised of 80% iron and 20% carbon nuclei with ⟨A⟩=48, the highest-⟨A⟩ target used to date in the study of this coherent reaction. The total cross section for coherent neutral-current single π0 production initiated by the νμ flux of the NuMI low-energy beam with mean (mode) Eν of 4.9 GeV (3.0 GeV), is 77.6±5.0(stat)−16.8+15.0(syst)×10−40 cm2 pernucleus. The results are in good agreement with predictions of the Berger-Sehgal model.
A study of charged-current muon neutrino scattering on hydrocarbon in which the final state includes a muon, at least one proton, and no pions is presented. Although this signature has the topology ...of neutrino quasielastic scattering from neutrons, the event sample contains contributions from quasielastic and inelastic processes where pions are absorbed in the nucleus. The analysis accepts events with muon production angles up to 70° and proton kinetic energies greater than 110 MeV. The cross section, when based completely on hadronic kinematics, is well described by a relativistic Fermi gas nuclear model including the neutrino event generator modeling for inelastic processes and particle transportation through the nucleus. This is in contrast to the quasielastic cross section based on muon kinematics, which is best described by an extended model that incorporates multinucleon correlations. As a result, this measurement guides the formulation of a complete description of neutrino-nucleus interactions that encompasses the hadronic as well as the leptonic aspects of this process.
We present a search for flavor changing neutral currents (FCNC) in decays of top quarks. The analysis is based on a search for \(t\bar{t}\rightarrow\ell'\nu\ell\bar{\ell}\)+jets (\(\ell, \ell' = ...e,\mu\)) final states using 4.1 {\rm fb}\(^{-1}\) of integrated luminosity of \(p\bar{p}\) collisions at \(\sqrt{s} = 1.96\) {\rm TeV}. We extract limits on the branching ratio \(B(t\rightarrow Zq)\) (\(q = u, c\) quarks), assuming anomalous \(tuZ\) or \(tcZ\) couplings. We do not observe any sign of such anomalous coupling and set a limit of \(B < 3.2%\) at 95% C.L.
We present measurements of the neutrino and antineutrino total charged-current cross sections on carbon and their ratio using the MINERvA scintillator-tracker. The measurements span the energy range ...2-22 GeV and were performed using forward and reversed horn focusing modes of the Fermilab low-energy NuMI beam to obtain large neutrino and antineutrino samples. The flux is obtained using a sub-sample of charged-current events at low hadronic energy transfer along with precise higher energy external neutrino cross section data overlapping with our energy range between 12-22 GeV. We also report on the antineutrino-neutrino cross section ratio, Rcc, which does not rely on external normalization information. Our ratio measurement, obtained within the same experiment using the same technique, benefits from the cancellation of common sample systematic uncertainties and reaches a precision of 5% at low energy. Our results for the antineutrino-nucleus scattering cross section and for Rcc are the most precise to date in the energy range \(E_{\nu} <\) 6GeV.
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