The ArgoNeuT collaboration presents measurements of inclusive muon neutrino and antineutrino charged current differential cross sections on argon in the Fermilab NuMI beam operating in the low energy antineutrino mode. The results are reported in terms of outgoing muon angle and momentum at a mean neutrino energy of 9.6 GeV (neutrinos) and 3.6 GeV (antineutrinos), in the range $0^\circ < \theta_\mu < 36^\circ$ and $0 < p_\mu < 25$ GeV/$c$, for both neutrinos and antineutrinos.
A high-statistics study by the Columbia-Chicago-Fermilab-Rochester Collaboration of opposite-sign dimuon events induced by neutrino-nucleon scattering at the Fermilab Tevatron is presented. A sample of 5044 νμ and 1062 ν¯μ induced μ∓μ± events with Pμ1≥9 GeV/c, Pμ2≥5 GeV/c, 30≤Eν≤600 GeV, and 〈Q2〉=22.2 GeV2/c2 is observed. The data support the slow-rescaling model of charm production with a value of mc=1.31±0.24 GeV2/c2. The first measurement of the Q2 dependence of the nucleon strange quark distribution xs(x) is presented. The data yield the Cabibbo-Kobayashi-Maskawa matrix element ‖Vcd‖=0.209±0.012 and the nucleon fractional strangeness content ηs=0.064−0.007+0.008.
We present a new measurement of the difference between the nucleon strange and antistrange quark distributions from dimuon events recorded by the NuTeV experiment at Fermilab. This analysis is the first to use a complete next to leading order QCD d escription of charm production from neutrino scattering. Dimuon events in neutrino deep inelastic scattering allow direct and independent study of the strange and antistrange content of the nucleon. We find a positive strange asymmetry with a significance of 1.6sigma . We also report a new measurement of the charm mass.
The NuTeV experiment at Fermilab has obtained a unique high statistics sample of neutrino and anti-neutrino interactions using its high-energy sign-selected beam. We present a measurement of the differential cross section for charged-current neutrino and anti-neutrino scattering from iron. Structure functions, F_2(x,Q^2) and xF_3(x,Q^2), are determined by fitting the inelasticity, y, dependence of the cross sections. This measurement has significantly improved systematic precision as a consequence of more precise understanding of hadron and muon energy scales.
We extract a set of values for the Gross-Llewellyn Smith sum rule at different values of 4-momentum transfer squared ($Q^{2}$), by combining revised CCFR neutrino data with data from other neutrino deep-inelastic scattering experiments for $1 < Q^2 < 15 GeV^2/c^2$. A comparison with the order $\alpha^{3}_{s}$ theoretical predictions yields a determination of $\alpha_{s}$ at the scale of the Z-boson mass of $0.114 \pm^{.009}_{.012}$. This measurement provides a new and useful test of perturbative QCD at low $Q^2$, because of the low uncertainties in the higher order calculations.
From analysis of V0 events observed in an exposure of the National Accelerator Laboratory 30-in. bubble chamber to 303−GeVc protons, we obtain these results: (1) 〈nπ0〉 rises approximately linearly with n-, implying strong coupling of neutral and charged pions, while 〈nKS0〉 is less coupled to n; (2) γ, KS0, and Λ0 production cross sections are approaching a scaling limit by 303 GeVc; (3) within the limited statistics, dσdy is flat in the central region for KS0 and low-multiplicity γ events.
We have measured the single-particle inclusive cross sections for p+p→π±+X, K±+X, p+X, p¯+X in the low-p⊥ region (≲ 1.5 GeV/c) as a function of the radial scaling variable XR in p−p collisions at 100, 200, and 400 GeV at Fermilab. The measured π+π− and K+K− ratios are shown to be remarkably similar to the same ratios which have recently been measured at large p⊥ at 90° in the center-of-mass system.
We report on the first observation of open charm production in neutral current deep inelastic neutrino scattering as seen in the NuTeV detector at Fermilab. The production rate is shown to be consistent with a pure gluon-$% Z^{0}$ boson production model, and the observed level of charm production is used to determine the effective charm mass. As part of our analysis, we also obtain a new measurement for the proton-nucleon charm production cross section at $\sqrt{s}=38.8$ GeV.
We present evidence for the diffractive processes nu_mu Fe -> mu^- D_s^+ (D_s^*+) Fe and nubar_mu Fe -> mu^+ D_s^- (D_s^*-) Fe using the Fermilab SSQT neutrino beam and the Lab E neutrino detector. We observe the neutrino trident reactions nu_mu Fe -> nu_mu mu^- mu^+ Fe and nubar_mu Fe -> nubar_mu mu^+ mu^- Fe at rates consistent with Standard Model expectations. We see no evidence for neutral-current production of J/psi via either diffractive or deep inelastic scattering mechanisms.
We present measurements of the semi-inclusive cross sections for νμ- and ν¯μ-nucleon deep inelastic scattering interactions with two oppositely charged muons in the final state. These events dominantly arise from the production of a charm quark during the scattering process. The measurement was obtained from the analysis of 5102 νμ-induced and 1458 ν¯μ-induced events collected with the NuTeV detector exposed to a sign-selected beam at the Fermilab Tevatron. We also extract a cross-section measurement from a reanalysis of 5030 νμ-induced and 1060 ν¯μ-induced events collected from the exposure of the same detector to a quad-triplet beam by the Chicago Columbia Fermilab Rochester (CCFR) experiment. The results are combined to obtain the most statistically precise measurement of neutrino-induced dimuon production cross sections to date. These measurements should be of broad use to phenomenologists interested in the dynamics of charm production, the strangeness content of the nucleon, and the Cabibbo-Kobayashi-Maskawa matrix element Vcd.
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