587 research outputs found
Reply to 'Corrections to the HARP-CDP Analysis of the LSND Neutrino Oscillation Backgrounds'
The alleged mistakes in recent papers that reanalyze the backgrounds to the
'LSND anomaly' do not exist. We maintain our conclusion that the significance
of the 'LSND anomaly' is not 3.8 sigma but not larger than 2.3 sigma.Comment: 3 page
Revisiting the 'LSND anomaly' II: critique of the data analysis
This paper, together with a preceding paper, questions the so-called 'LSND
anomaly': a 3.8 sigma excess of antielectronneutrino interactions over standard
backgrounds, observed by the LSND Collaboration in a beam dump experiment with
800 MeV protons. That excess has been interpreted as evidence for the
antimuonneutrino to antielectronneutrino oscillation in the \Deltam2 range from
0.2 eV2 to 2 eV2. Such a \Deltam2 range is incompatible with the widely
accepted model of oscillations between three light neutrino species and would
require the existence of at least one light 'sterile' neutrino. In a preceding
paper, it was concluded that the estimates of standard backgrounds must be
significantly increased. In this paper, the LSND Collaboration's estimate of
the number of antielectronneutrino interactions followed by neutron capture,
and of its error, is questioned. The overall conclusion is that the
significance of the 'LSND anomaly' is not larger than 2.3 sigma.Comment: 30 pages, 16 figures, 6 table
Why the paper CERN-PH-EP-2009-015 (arXiv:0903.4762) is scientifically unacceptable
The paper CERN-PH-EP-2009-015 (arXiv:0903.4762) by A. Bagulya et al. violates
standards of quality of work and scientific ethics on several counts. The paper
contains assertions that contradict established detector physics. The paper
falls short of proving the correctness of the authors' concepts and results.
The paper ignores or quotes misleadingly pertinent published work. The paper
ignores the fact that the authors' concepts and results have already been shown
wrong in the published literature. The authors seem unaware that cross-section
results from the 'HARP Collaboration' that are based on the paper's concepts
and algorithms are in gross disagreement with the results of a second analysis
of the same data, and with the results of other experiments.Comment: 8 pages, 3 figure
Cross-sections of large-angle hadron production in proton- and pion-nucleus interactions VII: tin nuclei and beam momenta from \pm3 GeV/c to \pm15 GeV/c
We report on double-differential inclusive cross-sections of the production
of secondary protons, charged pions, and deuterons, in the interactions with a
5% nuclear interaction length thick stationary tin target, of proton and pion
beams with momentum from \pm3 GeV/c to \pm15 GeV/c. Results are given for
secondary particles with production angles between 20 and 125 degrees.
Cross-sections on tin nuclei are compared with cross-sections on beryllium,
carbon, copper, tantalum and lead nuclei.Comment: 68 pages, 13 figure
Comparison of Geant4 hadron generation with data from the interactions with beryllium nuclei of +8.9 GeV/c protons and pions, and of -8 GeV/c pions
Hadron generation in the Geant4 simulation tool kit is compared with
inclusive spectra of secondary protons and pions from the interactions with
beryllium nuclei of +8.9 GeV/c protons and pions, and of -8.0 GeV/c pions. The
data were taken in 2002 at the CERN Proton Synchrotron with the HARP
spectrometer. We report on significant disagreements between data and simulated
data especially in the polar-angle distributions of secondary protons and
pions.Comment: 15 pages, 13 figure
Charged current events with neutral strange particles in high-energy antineutrino interactions
The results of a study of strange particle production in charged current interactions in the Fermilab 15 ft bubble chamber filled with a heavy Ne---H2 mixture are presented. Production rates and average multiplicities of K0's and [Lambda]'s as functions of W2 and Q2 are given. The experimental data agree well with the quark-parton model predictions if a yield of 0.06 +/- 0.02 of K0's and [Lambda]'s from charm production is included. Upper limits for D-meson production are given and the shape of the charmed quark fragmentation function is discussed. Inclusive production of the K*(890) and [Sigma](1385) resonances is measured and it is shown that only about 5% of the K0 mesons and [Lambda] hyperons results from resonance decays. Relative production rates of neutral strange particles on proton and neutron targets are studied.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24478/1/0000753.pd
Transverse-target-spin asymmetry in exclusive -meson electroproduction
Hard exclusive electroproduction of mesons is studied with the
HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and
electron beams off a transversely polarized hydrogen target. The amplitudes of
five azimuthal modulations of the single-spin asymmetry of the cross section
with respect to the transverse proton polarization are measured. They are
determined in the entire kinematic region as well as for two bins in photon
virtuality and momentum transfer to the nucleon. Also, a separation of
asymmetry amplitudes into longitudinal and transverse components is done. These
results are compared to a phenomenological model that includes the pion pole
contribution. Within this model, the data favor a positive
transition form factor.Comment: DESY Report 15-14
Cross-Sections of Large-Angle Hadron Production in Proton- and Pion-Nucleus Interactions V: Lead Nuclei and Beam Momenta from +/-3 Gev/c to +/-15 Gev/c
We report on double-differential inclusive cross-sections of the production
of secondary protons, charged pions, and deuterons, in the interactions with a
5% nuclear interaction length thick stationary lead target, of proton and pion
beams with momentum from +/-3 GeV/c to +/-15 GeV/c. Results are given for
secondary particles with production angles 20 to 125 degrees. Cross-sections on
lead nuclei are compared with cross-sections on beryllium, copper, and tantalum
nuclei.Comment: 67 pages, 13 figures, 47 table
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