664 research outputs found
Estimation of Sex from the Talus in Prehistoric Native Americans
We present both a multivariate discriminant analysis and a univariate procedure to estimate sex from measures of the talus (length, width and height). Both methods are comparable in accuracy (about 85%), but the univariate procedure is preferred due to its
simplicity
Measurement of the Luminosity in the ZEUS Experiment at HERA II
The luminosity in the ZEUS detector was measured using photons from electron
bremsstrahlung. In 2001 the HERA collider was upgraded for operation at higher
luminosity. At the same time the luminosity-measuring system of the ZEUS
experiment was modified to tackle the expected higher photon rate and
synchrotron radiation. The existing lead-scintillator calorimeter was equipped
with radiation hard scintillator tiles and shielded against synchrotron
radiation. In addition, a magnetic spectrometer was installed to measure the
luminosity independently using photons converted in the beam-pipe exit window.
The redundancy provided a reliable and robust luminosity determination with a
systematic uncertainty of 1.7%. The experimental setup, the techniques used for
luminosity determination and the estimate of the systematic uncertainty are
reported.Comment: 25 pages, 11 figure
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Neutrino physics at very high energies
NAL presents the opportunity to expand our knowledge of neutrino interactions from energies of less than 10 GeV up to more than 300 GeV. We propose an exploratory experiment which is designed to emphasize the physics of very high energy interactions ({approx}300 GeV)
A measurement of from the Gross-Llewellyn Smith Sum Rule
We extract a set of values for the Gross-Llewellyn Smith sum rule at
different values of 4-momentum transfer squared (), by combining revised
CCFR neutrino data with data from other neutrino deep-inelastic scattering
experiments for . A comparison with the order
theoretical predictions yields a determination of
at the scale of the Z-boson mass of . This measurement
provides a new and useful test of perturbative QCD at low , because of the
low uncertainties in the higher order calculations.Comment: 4 pages, 4 figure
A Precise Measurement of the Weak Mixing Angle in Neutrino-Nucleon Scattering
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, , we obtain .Comment: 10 pages, Nevis Preprint #1498 (Submitted to Phys. Rev. Lett.
A High Statistics Search for Electron-Neutrino --> Tau-Neutrino Oscillations
We present new limits on nu_e to nu_tau and nu_e to nu_sterile oscillations
by searching for electron neutrino dissappearance in the high-energy wide-band
CCFR neutrino beam. Sensitivity to nu_tau appearance comes from tau decay modes
in which a large fraction of the energy deposited is electromagnetic. The beam
is composed primarily of muon neutrinos but this analysis uses the 2.3%
electron neutrino component of the beam. Electron neutrino energies range from
30 to 600 GeV and flight lengths vary from 0.9 to 1.4 km. This limit improves
the sensitivity of existing limits and obtains a lowest 90% confidence upper
limit in sin**2(2*alpha) of 9.9 x 10**(-2) at delta-m**2 of 125 eV**2.Comment: submitted to Phys. Rev. D. Rapid Com
Extraction of R = sigma_L/sigma_T from CCFR nu_mu-Fe and nubar_mu-Fe differential cross sections
We report on the extraction of R=sigma_L/sigma_T from CCFR nu_mu-Fe and
nubar_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 nu_mu scattering is in
agreement with R as measured in muon and electron scattering. All data on R for
Q^2 > 1 GeV^2 are in agreement with a NNLO QCD calculation which includes
target mass effects. We report on the first measurements of R in the low x and
Q^2 < 1 GeV^2 region (where an anomalous large rise in R for nuclear targets
has been observed by the HERMES collaboration).Comment: 4 pages, 4 figures, submitted to Phys. Rev. Let
New Measurements of Nucleon Structure Functions from CCFR/NuTeV
We report on the extraction of the structure functions F_2 and Delta xF_3 =
xF_3nu-xF_3nub from CCFR neutrino-Fe and antineutrino-Fe differential cross
sections. The extraction is performed in a physics model independent (PMI) way.
This first measurement for Delta xF_3, which is useful in testing models of
heavy charm production, is higher than current theoretical predictions. Within
5% the F_2 (PMI) values measured in neutrino and muon scattering are in
agreement with the predictions of Next-to-Leading-Order PDFs (using massive
charm production schemes), thus resolving the long-standing discrepancy between
the two measurements.Comment: 3 pages, Presented by Arie Bodek at DPF2000 Conference, Columbus,
Ohio, Aug. 200
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