69 research outputs found
Prospects for Antineutrino Running at MiniBooNE
We outline a program of antineutrino cross-section measurements necessary for
the next generation of neutrino oscillation experiments, that can be performed
with one year of data at MiniBooNE. We describe three independent methods of
constraining wrong-sign (neutrino) backgrounds in an antineutrino beam, and
their application to the MiniBooNE antineutrino cross section measurements.Comment: 3 pages, 0 figures, NuFact05 to be published in Nucl. Phys. B (Proc.
Supp.
Charged Current Single Pion Cross Section Measurement at MiniBooNE
We present MiniBooNE's preliminary numu charged-current single pion (CC1pi)
cross section measurement, calculated using the ratio to charge current
quasi-elastic (CCQE) events. We find the inclusive CC1pi cross section to be
below the predcition of the NUANCE and NEUGEN Monte Carlos.Comment: 6 pages, 6 figures, proceedings from NuInt0
NUISANCE: a neutrino cross-section generator tuning and comparison framework
NUISANCE is an open source C++ framework which facilitates detailed studies of neutrino interaction cross-section models implemented in Monte Carlo neutrino event generators. It provides a host of automated methods to perform comparisons of multiple generators to published cross-section measurements and each other. External reweighting libraries are used to allow the end-user to evaluate the impact of model parameters variations in the generators with data, or to tune the generator predictions to arbitrary dataset combinations. The design is modular and focusses on ease-of-use to allow new datasets and more generators to be added without requiring detailed understanding of the entire NUISANCE package. We discuss the motivation for the NUISANCE framework and suggested usage cases, alongside a description of its core structure
Recent Measurements of Neutrino-Nucleus Quasi-Elastic Scattering
We present recent measurements of neutrino charged current quasi-elastic (CC
QE) scattering, nu_mu + p -> mu- + n. Measurements of CC QE on carbon near 1
GeV by MiniBooNE and SciBooNE, as well as measurements on iron at 3 GeV by
MINOS, disagree with current interaction models, while measurements at higher
energies on carbon by NOMAD show excellent agreement with those same models.Comment: 5 pages, 3 figures, proceedings from Neutrino 201
Milagrito: a TeV air-shower array
Milagrito, a large, covered water-Cherenkov detector, was the world's first
air-shower-particle detector sensitive to cosmic gamma rays below 1 TeV. It
served as a prototype for the Milagro detector and operated from February 1997
to May 1998. This paper gives a description of Milagrito, a summary of the
operating experience, and early results that demonstrate the capabilities of
this technique.Comment: 38 pages including 24 figure
First Observation of Coherent Production in Neutrino Nucleus Interactions with 2 GeV
The MiniBooNE experiment at Fermilab has amassed the largest sample to date
of s produced in neutral current (NC) neutrino-nucleus interactions at
low energy. This paper reports a measurement of the momentum distribution of
s produced in mineral oil (CH) and the first observation of coherent
production below 2 GeV. In the forward direction, the yield of events
observed above the expectation for resonant production is attributed primarily
to coherent production off carbon, but may also include a small contribution
from diffractive production on hydrogen. Integrated over the MiniBooNE neutrino
flux, the sum of the NC coherent and diffractive modes is found to be (19.5
1.1 (stat) 2.5 (sys))% of all exclusive NC production at
MiniBooNE. These measurements are of immediate utility because they quantify an
important background to MiniBooNE's search for
oscillations.Comment: Submitted to Phys. Lett.
Theoretical study of lepton events in the atmospheric neutrino experiments at SuperK
Super-Kamiokande has reported the results for the lepton events in the
atmospheric neutrino experiment. These results have been presented for a 22.5kT
water fiducial mass on an exposure of 1489 days, and the events are divided
into sub-GeV, multi-GeV and PC events. We present a study of nuclear medium
effects in the sub-GeV energy region of atmospheric neutrino events for the
quasielastic scattering, incoherent and coherent pion production processes, as
they give the most dominant contribution to the lepton events in this energy
region. We have used the atmospheric neutrino flux given by Honda et al. These
calculations have been done in the local density approximation. We take into
account the effect of Pauli blocking, Fermi motion, Coulomb effect,
renormalization of weak transition strengths in the nuclear medium in the case
of the quasielastic reactions. The inelastic reactions leading to production of
leptons along with pions is calculated in a - dominance model by
taking into account the renormalization of properties in the nuclear
medium and the final state interaction effects of the outgoing pions with the
residual nucleus. We present the results for the lepton events obtained in our
model with and without nuclear medium effects, and compare them with the Monte
Carlo predictions used in the simulation and the experimentally observed events
reported by the Super-Kamiokande collaboration.Comment: 23 pages, 13 figure
Measurement of and charged current inclusive cross sections and their ratio with the T2K off-axis near detector
We report a measurement of cross section and the first measurements of the cross section
and their ratio
at (anti-)neutrino energies below 1.5
GeV. We determine the single momentum bin cross section measurements, averaged
over the T2K -flux, for the detector target material (mainly
Carbon, Oxygen, Hydrogen and Copper) with phase space restricted laboratory
frame kinematics of 500 MeV/c. The
results are and $\sigma(\nu)=\left( 2.41\
\pm0.022{\rm{(stat.)}}\pm0.231{\rm (syst.)}\ \right)\times10^{-39}^{2}R\left(\frac{\sigma(\bar{\nu})}{\sigma(\nu)}\right)=
0.373\pm0.012{\rm (stat.)}\pm0.015{\rm (syst.)}$.Comment: 18 pages, 8 figure
Test of Lorentz and CPT violation with Short Baseline Neutrino Oscillation Excesses
The sidereal time dependence of MiniBooNE electron neutrino and anti-electron
neutrino appearance data are analyzed to search for evidence of Lorentz and CPT
violation. An unbinned Kolmogorov-Smirnov test shows both the electron neutrino
and anti-electron neutrino appearance data are compatible with the null
sidereal variation hypothesis to more than 5%. Using an unbinned likelihood fit
with a Lorentz-violating oscillation model derived from the Standard Model
Extension (SME) to describe any excess events over background, we find that the
electron neutrino appearance data prefer a sidereal time-independent solution,
and the anti-electron neutrino appearance data slightly prefer a sidereal
time-dependent solution. Limits of order 10E-20 GeV are placed on combinations
of SME coefficients. These limits give the best limits on certain SME
coefficients for muon neutrino to electron neutrino and anti-muon neutrino to
anti-electron neutrino oscillations. The fit values and limits of combinations
of SME coefficients are provided.Comment: 14 pages, 3 figures, and 2 tables, submitted to Physics Letters
Search for Lorentz and CPT violation using sidereal time dependence of neutrino flavor transitions over a short baseline
A class of extensions of the Standard Model allows Lorentz and CPT violations, which can be identified
by the observation of sidereal modulations in the neutrino interaction rate. A search for such modulations
was performed using the T2K on-axis near detector. Two complementary methods were used in this study,
both of which resulted in no evidence of a signal. Limits on associated Lorentz and CPT-violating terms
from the Standard Model extension have been derived by taking into account their correlations in this
model for the first time. These results imply such symmetry violations are suppressed by a factor of more
than 10 20 at the GeV scale
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