Search

The NuTeV experiment at Fermilab has obtained a unique high statistics sample of neutrino and antineutrino interactions using a novel high-energy sign-selected neutrino beam. Recent results from this sample are presented including a precision measurement of the electroweak parameter sin2≡W, which is observed to be three standard deviations above the standard model prediction.

NuTeV measures sin 2 θ W by comparing neutral and charged current cross-sections on a heavy nuclear target, and finds a value of sin 2 θ W (on-shell) = 0.2277 ± 0.0013(stat) ± 0.0009(syst), approximately 3σ from the predicted value. We discuss the possibility that nuclear effects on parton distribution functions or cross-sections may be responsible for the discrepancy.

A new structure function analysis of CCFR deep inelastic nu-N and nu-N scattering data is presented for previously unexplored kinematic regions down to Bjorken x = 0.0045 and Q(2) = 0.3 GeV(2). Comparisons to charged lepton scattering data from NMC and E665 experiments are made and the behavior of the structure function F(2)(nu)2 is studied in the limit Q(2)-->0.

We report on the extraction of the structure functions F2 and DeltaxF(3) = xF(nu)(3)-xF(nu;)(3) from CCFR nu(mu)-Fe and nu;(mu)-Fe differential cross sections. The extraction is performed in a physics model-independent (PMI) way. This first measurement of DeltaxF(3), which is useful in testing models of heavy charm production, is higher than current theoretical predictions. The ratio of the F2 (PMI) values measured in nu(mu) and mu scattering is in agreement (within 5%) with the predictions of next-to-leading-order parton distribution functions using massive charm production schemes, thus resolving the long-standing discrepancy between the two sets of data.

Fermilab experiments CCFR and its successor NuTeV study nucleon structure through deep inelastic scattering of neutrino beams off an iron target. We report on the most recent CCFR measurement of the νN differential cross section and resulting structure functions ΔxF 3 = xF ν 3 − xF ν 3 , and R long = σ L σ T , in the framework of massive charm quark. ΔxF3 in sensitive to strange and charm content of the nucleon. NuTeV's preliminary direct measurement of the strange sea, from dimuon charged-current production, and nucleon charm content probed by neutral-current νN interaction, are also presented.

We report on a measurement of the neutrino-nucleon and antineutrino-nucleon differential cross sections in the CCFR detector. The measurement of the differential cross sections over a wide range of energies allows ΔχF 3 = χF 3 ν −χF 3 v and R to be extracted. ΔχF3 is related to the difference between the contributions of the strange and charm seas in the nucleon to production of massive charm quark. The results for ΔχF3 are compared to various massive charm NLO QCD models. The Q2 dependence of R for χ

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 $1l{Q}^{2}l15{\mathrm{GeV}}^{2}{/c}^{2}$. A comparison with the order ${\ensuremath{\alpha}}_{s}^{3}$ theoretical predictions yields a determination of ${\ensuremath{\alpha}}_{s}$ at the scale of the $Z$-boson mass of $0.114{\ifmmode\pm\else\textpm\fi{}}_{0.012}^{0.009}$. 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.

We present an improved determination of the proton structure functions $F_{2}$ and $xF_{3}$ from the CCFR $\nu $-Fe deep inelastic scattering (DIS) experiment. Comparisons to high-statistics charged-lepton scattering results for $F_{2}$ from the NMC, E665, SLAC, and BCDMS experiments, after correcting for quark-charge and heavy-target effects, indicate good agreement for $x>0.1$ but some discrepancy at lower x. The $Q^{2}$ evolution of the structure functions yields the quantum chromodynamics (QCD) scale parameter $\Lambda_{\bar{MS}}^{NLO,(4)}=337 \pm 28$(exp.) MeV. This corresponds to a value of the strong coupling constant at the scale of mass of the Z-boson of $\alpha _{S}(M_{Z}^{2})=0.119 \pm 0.002 (exp.) \pm 0.004 (theory)$ and is one of the most precise measurements of this quantity.

Previous energy measurements of cosmic ray muons have used magnetic spectrometers to measure the momentum of muons. Measurements using magnets fail for muons in the TeV range because at ultra-high muon energies, the measurement error in the angular deflection of muons by the spectrometer becomes comparable to the total angula deflection. A new method for measuring the energies of TeV muons is investigated, using a sample of cosmic ray muons accumulated parasitically (or synergistically) by the CCFR neutrino detector. The method infers the muon energy from measurements of the energy deposited by the muon in many layers of an iron-scintillator calorimeter. Muons in the TeV energy range lose energy stochastically through e+et - pai production. The distribution of muon energy loss is used t estimate the most likely muon energy. The analysis suggest that this new method for measuring cosmic ray muon energ may be applicable in future detectors such as MINOS an AMANDA.

Limits on ${\ensuremath{\nu}}_{\ensuremath{\mu}}({\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})\ensuremath{\rightarrow}{\ensuremath{\nu}}_{e}({\overline{\ensuremath{\nu}}}_{e})$ oscillations based on a statistical separation of ${\ensuremath{\nu}}_{e}N$ charged current interactions in the CCFR detector at Fermilab are presented. Neutrino energies range from 30 to 600 GeV with a mean of 140 GeV, and ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ flight lengths vary from 0.9 to 1.4 km. The result excludes oscillations in the region with ${sin}^{2}2\ensuremath{\alpha}g1.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ for large $\ensuremath{\Delta}{m}^{2}(g1000{\mathrm{eV}}^{2})$ and $\ensuremath{\Delta}{m}^{2}g1.6{\mathrm{eV}}^{2}$ for ${sin}^{2}2\ensuremath{\alpha}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$. This result is the most stringent limit to date for $\ensuremath{\Delta}{m}^{2}g25{\mathrm{eV}}^{2}$ and it excludes the high $\ensuremath{\Delta}{m}^{2}$ oscillation region favored by the LSND experiment. The ${\ensuremath{\nu}}_{\ensuremath{\mu}}$-to- ${\ensuremath{\nu}}_{e}$ cross-section ratio was measured as a test of ${\ensuremath{\nu}}_{\ensuremath{\mu}}({\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})\ensuremath{\leftrightarrow}{\ensuremath{\nu}}_{e}({\overline{\ensuremath{\nu}}}_{e})$ universality to be $1.026\ifmmode\pm\else\textpm\fi{}0.025(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.049(\mathrm{syst})$.

We present limits on ${\ensuremath{\nu}}_{\ensuremath{\mu}}({\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})\ensuremath{\rightarrow}{\ensuremath{\nu}}_{\ensuremath{\tau}}({\overline{\ensuremath{\nu}}}_{\ensuremath{\tau}})$ and ${\ensuremath{\nu}}_{\ensuremath{\mu}}({\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})\ensuremath{\rightarrow}{\ensuremath{\nu}}_{e}({\overline{\ensuremath{\nu}}}_{e})$ oscillations based on a study of inclusive $\ensuremath{\nu}N$ interactions performed using the CCFR massive coarse-grained detector in the Fermilab Tevatron Quadrupole Triplet neutrino beam. The sensitivity to oscillations is from the difference in the longitudinal energy deposition pattern of ${\ensuremath{\nu}}_{\ensuremath{\mu}}N$ vs ${\ensuremath{\nu}}_{\ensuremath{\tau}}N$ or ${\ensuremath{\nu}}_{e}N$ charged-current interactions. The ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ energies ranged from 30 to 500 GeV with a mean of 140 GeV. The minimum and maximum ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ flight lengths are 0.9 and 1.4 km, respectively. For ${\ensuremath{\nu}}_{\ensuremath{\mu}}\ensuremath{\rightarrow}{\ensuremath{\nu}}_{\ensuremath{\tau}}$ oscillations, the lowest 90% confidence upper limit in ${sin}^{2}2\ensuremath{\alpha}$ of 2.7 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}3}$ is obtained at $\ensuremath{\Delta}{m}^{2}\ensuremath{\sim}50$ e${\mathrm{V}}^{2}$. This result is the most stringent limit to date for $25l\ensuremath{\Delta}{m}^{2}l90$ e${\mathrm{V}}^{2}$. For ${\ensuremath{\nu}}_{\ensuremath{\mu}}\ensuremath{\rightarrow}{\ensuremath{\nu}}_{e}$ oscillations, the lowest 90% confidence upper limit in ${sin}^{2}2\ensuremath{\alpha}$ of 1.9 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}3}$ is obtained at $\ensuremath{\Delta}{m}^{2}\ensuremath{\sim}350$ e${\mathrm{V}}^{2}$. This result is the most stringent limit to date for $250l\ensuremath{\Delta}{m}^{2}l450$ e${\mathrm{V}}^{2}$, and also excludes at 90% confidence much of the high $\ensuremath{\Delta}{m}^{2}$ region favored by the recent LSND observation.

Results from the high-energy, high-statistics studies of neutrino nucleon interactions by the CCFR collaboration at the Fermilab Tevatron are described. Using a data sample of over 3.7 million events with energies up to 600 GeV, precision measurements are presented for the weak mixing angle, sin 2 θ w , the structure functions, F 2 ( χ, Q 2 ) and χ F 3 ( χ, Q 2 ), and the strange quark distribution, χs ( χ, Q 2 ). Comparisons of these measurements to those obtained in other processes are made in the context of global electroweak and QCD tests. Prospects for the next generation measurements by the NuTeV collaboration at Fermilab are also presented.

We report a precise measurement of the weak mixing angle from the ratio of neutral current to charged current inclusive cross-sections in deep-inelastic neutrino-nucleon scattering. The data were gathered at the CCFR neutrino detector in the Fermilab quadrupole-triplet neutrino beam, with neutrino energies up to 600 GeV. Using the on-shell definition, ${\rm sin ^2\theta_W} \equiv 1 - \frac{{\rm M_W} ^2}{{\rm M_Z} ^2}$, we obtain ${\rm sin ^2\theta_W} = 0.2218 \pm 0.0025 ({\rm stat.}) \pm 0.0036 ({\rm exp.\: syst.}) \pm 0.0040 ({\rm model})$., Comment: 10 pages, Nevis Preprint #1498 (Submitted to Phys. Rev. Lett.)

We have extracted the momentum dependence of the mean, the truncated mean and the most probable value of the energy deposited in a segmented, iron-scintillator, hadron calorimeter by high-energy muons. Data were drawn from a sample of momentum-analyzed, high-energy muons produced in charged-current neutrino interactions. The truncated mean energy deposition of high-energy muons traversing 20 calorimeter segments increases by approximately 16% per 100 GeV c increase in muon momentum over the range 25−125 GeV c ; the most probable energy deposition increases by approximately 7%. These results are important for experiments at high-energy colliders (e.g., Tevatron, SSC and LHC) which use the d E d x of high-energy muons to calibrate the response of electromagnetic and hadron calorimeters with tower geometry. The data are in qualitative agreement with GEANT3 (v3.15/308a) simulations.

We report energy and angle resolutions for hadron showers produced in the CCFR iron target-calorimeter. The measurements were made using drift chambers instrumented with FADC readout; showers were produced using a momentum-analyzed hadron test beam from the Fermilab Tevatron at energies of 40, 70, 100, 150, and 200 GeV. Shower energy measurements are compared to measurements using scintillation counters in the same target.

We report a measurement of the Gross-Llewellyn Smith sum rule: ∫( 1 x ) d x xF 3 (x, Q 2 =3 GeV 2 )=2.50±0.018( stat. ) ±0.078( syst. ) .

The CCFR Collaboration presents a measurement of scaling violations of the nonsinglet structure function and a comparison to the predictions of perturbative QCD. The value of [Lambda][sub QCD], from the nonsinglet evolution with [ital Q][sup 2][gt]15 GeV[sup 2] and in the modified minimal-subtraction renormalization scheme, is found to be 210[plus minus]28(stat)[plus minus]41(syst) MeV.

We present measurements of nucleon structure functions, F2(ϰ, Q2) and xFs(ϰ, Q2), from the high-statistics, high-energy neutrino-iron scattering experiment at the Fermilab Tevatron. The existing high-statistics xF3 determination by the CDHSW collaboration is compared to our data. The data presented here constitute the first corroboration of the QCD prediction of xF3 evolution at low-ϰ, and yields ΛMS=210±28±41 MeV, and a determination of the GLS sum rule at Q2 = 3 GeV2, SGLS = ∫ϰ1xFsϰ=2.50±0.018 (stat.)±0.078 (syst.). Our value of ΛMS yields α3(Mz) = .111 ± .002 ± .003 ± .003 (scale). Comparison of the neutrino determination of F2(ϰ, Q2) with that obtained from the charged-lepton (e or μ) scattering leads to a precise test of the mean-square charge prediction by the Quark Parton Model. The SLAC-CCFR and BCDMS structure function provide a consistent and precise set of structure functions over a large range of Q2.

We present the results of a preliminary determination of sin 2 θ W from a study of vFe scattering in the Lab E detector at Fermilab. The analysis is based on a sample of 5 × 10 5 events with a mean neutrino energy of 166 GeV. Our result, sin 2 θ W = 0.2242 ± 0.0044 expt . ± 0.0047 model , is the highest energy high statistics determination of the weak mixing angle using neutrino data.

Neutrino and antineutrino interactions with two muons in the final state have been studied by the CCFR collaboration in the Fermilab Tevatron neutrino beam. The rate of neutrino- and antineutrino-induced prompt same-sign dimuon production in steel was measured using a sample of 220 μ−μ− events and 15 μ+μ+ events with Pμ > 9 GeV/c, and energies between 30 GeV and 600 GeV. After background subtraction, the prompt rate of same-sign dimuon production is (0.53 ± 0.24) × 10−4 per νμ charged-current event and (0.52 ± 0.33) × 10 −4 per ν μ charged-current event. After demanding Pμ1 ≥ 9 GeV/c, Pμ2 ≥ 5 GeV/c and 30 ≤ Eν ≤ 600 GeV a sample of 5044 ν μ 1062 ν μ induced μ ∓ μ ± events are observed. The data support the slow rescaling model of charm production with a value of mc = 1.31 ± .24 GeV/c2. The CKM matrix element Vcd=.209±0.012 and the nucleon strangeness content, ηe=.064−0.00065+0.00075 are measured with the strange sea x distribution found to be softer than its non-strange counterpart. The first measurements of the Q2 dependence of the strange quark densities, ϰs(ϰ), are also presented.

The rate of neutrino- and antineutrino-induced prompt same-sign dimuon production in steel was measured using a sample of μ−μ− events and 25 μ+μ+ events withPμ>9 GeV/c, produced in 1.5 millionvμ and 0.3 million\(\overline {v_\mu }\) induced charged-current events with energies between 30 GeV and 600 GeV. The data were obtained with the Chicago-Columbia-Fermilab-Rochester (CCFR) neutrino detector in the Fermilab Tevatron Quadrupole Triplet Neutrino Beam during experiments E 744 and E 770. After background subtraction, the prompt rate of same-sign dimuon production is (0.53±0.24)×10−4 pervμ charged-current event and (0.52±0.33)×10−4 per\(\overline {v_\mu }\) charged-current event. The kinematic distributions of the same-sign dimuon events after background subtraction are consistent with those of the non-prompt background due to meson decays in the hadron shower of a charged-current event. Calculations ofc\(\bar c\) gluon bremsstrahlung, based on improved measurements of the charm mass parameter and nucleon structure functions by the CCFR collaboration, yield a prompt rate of (0.09±0.39)×10−4 pervμ charged-current event. In this case,c\(\bar c\) gluon bremsstrahlung is probably not an observable source of prompt same-sign dimuons.

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 ${\ensuremath{\nu}}_{\mathrm{\ensuremath{\mu}}}$ and 1062 \ensuremath{\nu}${\mathrm{\ifmmode\bar\else\textasciimacron\fi{}}}_{\mathrm{\ensuremath{\mu}}}$ induced ${\mathrm{\ensuremath{\mu}}}^{\ensuremath{\mp}}$${\mathrm{\ensuremath{\mu}}}^{\ifmmode\pm\else\textpm\fi{}}$ events with ${\mathit{P}}_{\mathrm{\ensuremath{\mu}}1}$\ensuremath{\ge}9 GeV/c, ${\mathit{P}}_{\mathrm{\ensuremath{\mu}}2}$\ensuremath{\ge}5 GeV/c, 30\ensuremath{\le}${\mathit{E}}_{\ensuremath{\nu}}$\ensuremath{\le}600 GeV, and 〈${\mathit{Q}}^{2}$〉=22.2 ${\mathrm{GeV}}^{2}$/${\mathit{c}}^{2}$ is observed. The data support the slow-rescaling model of charm production with a value of ${\mathit{m}}_{\mathit{c}}$=1.31\ifmmode\pm\else\textpm\fi{}0.24 ${\mathrm{GeV}}^{2}$/${\mathit{c}}^{2}$. The first measurement of the ${\mathit{Q}}^{2}$ dependence of the nucleon strange quark distribution xs(x) is presented. The data yield the Cabibbo-Kobayashi-Maskawa matrix element \ensuremath{\Vert}${\mathit{V}}_{\mathit{c}\mathit{d}}$\ensuremath{\Vert}=0.209\ifmmode\pm\else\textpm\fi{}0.012 and the nucleon fractional strangeness content ${\mathrm{\ensuremath{\eta}}}_{\mathit{s}}$=0.${064}_{\mathrm{\ensuremath{-}}0.007}^{+0.008}$.

We report on a search for flavor-changing neutral-currents (FCNC) in the production of heavy quarks in deep inelastic νμN and [Formula: see text] scattering by the NuTeV experiment at the Fermilab Tevatron. This measurement, made possible by the high-purity NuTeV sign-selected beams, probes for FCNC in heavy flavors at the quark level and is uniquely sensitive to neutrino couplings of potential FCNC mediators. All searches are consistent with zero, and limits on the effective mixing strengths |Vus|2, |Vdb|2, and |Vsb|2 are obtained.

A search for the decay of long-lived neutral particles has been performed using an instrumented decay channel at the E815 (NuTeV) experiment at Fermilab. The data were examined for particles decaying into the muonic final states μμ, μe, and μπ. Three μμ events were observed over an expected background of 0.040±0.009 events; no events were observed in the other modes. No Standard Model process appears to be consistent with this observation.

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-Z0 boson production model, and the observed level of charm production is used to determine the effective charm mass.

This paper describes the design and parameters of a quadrupole mirror structure for testing the mechanical, thermal and quench performance of single shell-type superconducting quadrupole coils at field, current and force levels similar to that of real magnet. The concept was experimentally verified by testing two quadrupole coils, previously used in quadrupole models, in the developed mirror structure in the temperature range from 4.5 to 1.9 K. The coils were instrumented with voltage taps, heaters, and strain gauges to monitor their mechanical and thermal properties and quench performance. A new quadrupole coil made of improved Nb{sub 3}Sn RRP-108/127 strand and cable insulation based on E-glass tape was also tested using this structure. The fabrication and test results of the quadrupole mirror models are reported and discussed.

Novel configurations of helical superconducting magnets for muon beam 6D phase space cooling channels and demonstration experiments are being designed at Fermilab. Operating as needed for the beam cooling in a cryogenic environment, the helical solenoid generates longitudinal and transverse magnetic fields; meanwhile, large Lorentz forces are produced, so rigid coil support structures need to be designed. A short model of a helical solenoid (HS), consisting of four coils and supporting structures, was designed, built and tested at Fermilab. The magnetic and mechanical designs were analyzed using TOSCA and ANSYS. The supporting structures were fabricated and assembled using SSC NbTi cable. Strain gauges were utilized to monitor the deformation of the structures due to both thermal contraction and Lorentz forces. The superconducting coils were trained during the test. The model should prove the design concept, fabrication technology, and the magnet system performance.

The relative absence of \ensuremath{\nu}${\mathrm{\ifmmode\bar\else\textasciimacron\fi{}}}_{\mathrm{\ensuremath{\mu}}}$-induced charged current events with respect to ${\ensuremath{\nu}}_{\mathrm{\ensuremath{\mu}}}$-induced events at large (g0.45) and large y (g0.70) enables us to limit the right handed coupling of the weak current. Our data restrict \ensuremath{\Vert}\ensuremath{\eta}${\mathrm{\ensuremath{\Vert}}}^{2}$=\ensuremath{\Vert}${\mathit{g}}_{\mathit{R}}$/${\mathit{g}}_{\mathit{L}}$${\mathrm{\ensuremath{\Vert}}}^{2}$0.0 015 with 90% C.L. Within the framework of left-right symmetric models, this measurement imposes a limit upon the mixing angle of the left and right handed bosons. Unlike the limits imposed by the \ensuremath{\mu}-decay and nuclear \ensuremath{\beta}-decay experiments, our limit is valid irrespective of the mass of the right handed neutrino.

We have measured the longitudinal particle punchthrough probability from shower cascades produced by hadrons incident on the iron-scintillator calorimeter of the CCFR neutrino detector and have compared them to a Monte Carlo simulation. Measurements of the dE/dx energy loss iron of high energy cosmic ray muons (up to 1 TeV) incident on the same detector are presented and are compared against calculations.

We report on muon spectrometry at the CCFR neutrino detector. The muon spectrometer and momentum-fitting analysis code are described, and results presented from the calibration of the spectrometer with test beams of momentum-analyzed muons.

Preliminary measurements of structure functions have been made from a sample of 1,281,000 ν μ and 270,000 ν μ charged current events with 30 GeV σ( ν μ )/σ(ν μ ) = .511 ± .002 ( stat ) ± .005 ( syst ) , and an analysis of the Q2 evolution of xF3.

A series of 1-m long Nb3Sn dipole models has been built at Fermilab in an attempt to refine the wind-and-react technology for Nb3Sn accelerator magnets. Three models made with Powder-in-Tube Nb3Sn strand reached their design field of 10 T demonstrating a good reproducibility of magnet quench performance and field quality. Recently a new dipole “mirror” model based on Nb3Sn coil made of improved Restack Rod Process (RRP) strand was constructed and tested reaching the maximum field above 11 T. This paper describes the parameters of the RRP strand and cable used as well as the design, fabrication and test results of this magnet.

We report an improved measurement of the inverse muon decay process, νμ+e→μ−+νe, at the Fermilab Tevatron. The rate of this reaction with respect to the νμ-N charged current interaction is measured to be (0.1245±0.0057(stat.)±0.0031 (sys.)) × 10−2. The measurement confirms the standard model predictions for the Lorentz structure of the weak current, the helicity of the neutrino, and the energy dependence of the cross section.

The techniques used to calibrate and monitor the energy response of the CCFR (Lab E) iron-scintillator target calorimeter for a precision measurement of shower energies are described. Measurements on the energy response of the calorimeter to hadrons, electrons, and minimum ionizing muons (from range outs) are presented. The calorimeter's energy response and resolution for hadrons and electrons are obtained using a test beam with energies between 15 and 450 GeV.

We have measured the strange-quark content of the nucleon, {eta}{sub {ital s}}={sup +0.012}{sub {minus}0.08}, and the Kobayashi-Maskawa matrix element {vert bar}{ital V}{sub {ital c}{ital d}}{vert bar}=0.220{sup +0.015}{sub {minus}0.018} using a sample of 1797 {nu}{sub {mu}}- and {bar {nu}}{sub {mu}}-induced {mu}{sup {minus}}{mu}{sup +} events with {ital P}{sub {mu}}{ge}9 GeV/{ital c} and 30{le}{ital E}{sub {nu}}{le}600 GeV. The data are consistent with the slow-rescaling hypothesis of charm production in {nu}-{ital N} scattering and within this formalism yield a value of the charm-quark mass parameter {ital m}{sub {ital c}}=1.31{sub {minus}0.48}{sup +0.64} GeV/{ital c}{sup 2}.

We report on two recent measurements by the CCFR collaboration using the Fermilab Tevatron quad-triplet neutrino beam with neutrino energies up to 600 GeV. In a sample of 666,000 neutrino and 132,000 antineutrino events, 1151 inverse μ-decay events νμe− → μ−νe, were isolated corresponding to a rate with respect to ν μ-N charged current interactions of (0.125±.009 (stat.) ± .003 (sys.)) × 10−2. The data also contain 1522 νμ and 275 ν μ induced opposite sign dimuon events which are due predominantly to charm production at the hadronic vertex. Using this sample, we have measured the strange sea content of the nucleon, ηs = ∫ dχ(2χs(χ))/ ∫ dχ(χu(χ) + χd(χ)) = .057−0.008+0.012, the Cabbibo-KObayashi-Maskawa matrix element, |Vcd| = 0.220−.015+.018, and the slow-rescaling model charm mass parameter, mc = 1.3−0.5+0.6GeV. 0868

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., Comment: 27 pages, 12 figures. Source package includes NuTeV data (NuTeVPack); download at http://arxiv.org/e-print/hep-ex/0509010

The NuTeV experiment at Fermilab obtained pure high statistics samples of neutrino and antineutrino interactions using its sign‐selected beam. Preliminary inclusive charged current differential cross sections of neutrino and antineutrino interactions on iron are presented, along with preliminary measurements of F2(x, Q2) and xF3(x, Q2). Preliminary results from the next‐to‐leading order QCD analysis of deep inelastic charged current dimuon data are also shown.

The NuTeV collaboration recently reported a value of sin2thetaW measured in neutrino-nucleon scattering that is 3 standard deviations above the standard model prediction. This result is derived assuming that (1) the strange sea is quark-antiquark symmetric, s(x)=sbar(x), and (2) up and down quark distributions are symmetric under the simultaneous interchange of u d and p n. We report the impact of violations of these symmetries on sin2thetaW and discuss the theoretical and experimental constraints on such asymmetries.

Limits on nu(mu)-->nu(e) and nu(mu)-->nu(e) oscillations are extracted using the NuTeV detector with sign-selected nu(mu) and nu(mu) beams. In nu(mu) mode, for the case of sin(2)2alpha = 1, Delta(m)(2)>2.6 eV(2) is excluded, and for Delta(m)(2)>>1000 eV(2), sin(2)2alpha>1.1 x 10(-3). The NuTeV data exclude the high Delta(m)(2) end of nu(mu)-->nu(e) oscillation parameters favored by the LSND experiment without the need to assume that the oscillation parameters for nu and nu are the same. We present the most stringent experimental limits for nu(mu)(nu(mu))-->nu(e)(nu(e)) oscillations in the large Delta(m)(2) region.

Limits on nu(mu)--nu(e) and nu(mu)--nu(e) oscillations are extracted using the NuTeV detector with sign-selected nu(mu) and nu(mu) beams. In nu(mu) mode, for the case of sin(2)2alpha = 1, Delta(m)(2)2.6 eV(2) is excluded, and for Delta(m)(2)1000 eV(2), sin(2)2alpha1.1 x 10(-3). The NuTeV data exclude the high Delta(m)(2) end of nu(mu)--nu(e) oscillation parameters favored by the LSND experiment without the need to assume that the oscillation parameters for nu and nu are the same. We present the most stringent experimental limits for nu(mu)(nu(mu))--nu(e)(nu(e)) oscillations in the large Delta(m)(2) region.

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.

We report on the extraction of $R\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\frac{{\ensuremath{\sigma}}_{L}}{{\ensuremath{\sigma}}_{T}}$ from CCFR ${\ensuremath{\nu}}_{\ensuremath{\mu}}$-Fe and ${\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}}$-Fe differential cross sections. The CCFR differential cross sections do not show the deviations from the QCD expectations that are seen in the CDHSW data at very low and very high $x$. $R$ as measured in ${\ensuremath{\nu}}_{\ensuremath{\mu}}$ scattering is in agreement with $R$ as measured in muon and electron scattering. All data on $R$ for ${Q}^{2}g1{\mathrm{GeV}}^{2}$ are in agreement with a NNLO QCD calculation which uses NNLO parton distribution functions and includes target mass effects. We report on the first measurements of $R$ in the low $x$ and ${Q}^{2}l1{\mathrm{GeV}}^{2}$ region (where an anomalous large rise in $R$ for nuclear targets has been observed by the HERMES Collaboration).

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{sup 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 {radical}s=38.8 GeV.