46 research outputs found
First measurement of the muon neutrino charged current quasielastic double differential cross section
A high-statistics sample of charged-current muon neutrino scattering events collected with the MiniBooNE experiment is analyzed to extract the first measurement of the double differential cross section (d(2)sigma/dT(mu)dcos theta(mu)) for charged-current quasielastic (CCQE) scattering on carbon. This result features minimal model dependence and provides the most complete information on this process to date. With the assumption of CCQE scattering, the absolute cross section as a function of neutrino energy (sigma[E-nu]) and the single differential cross section (d sigma/dQ(2)) are extracted to facilitate comparison with previous measurements. These quantities may be used to characterize an effective axial-vector form factor of the nucleon and to improve the modeling of low-energy neutrino interactions on nuclear targets. The results are relevant for experiments searching for neutrino oscillations.This work was conducted with support from Fermilab,
the U.S. Department of Energy, and the National Science
Foundation.Peer reviewe
Nuclear effects in neutrino-nucleus interactions
An accurate description of the nuclear response functions for neutrino
scattering in the Gev region is essential for the interpretation of present and
future neutrino oscillation experiments. Due to the close similarity of
electromagnetic and weak scattering processes, we will review the status of the
scaling approach and of relativistic modeling for the inclusive electron
scattering response functions in the quasielastic and -resonance
regions. In particular, recent studies have been focused on scaling violations
and the degree to which these imply modifications of existing predictions for
neutrino reactions. We will discuss sources and magnitude of such violations,
emphasizing similarities and differences between electron and neutrino
reactions.Comment: 7 pages, 5 figures, Proceeding of the XVIII International School on
Nuclear Physics, Neutron Physics and Applications, September 21 - 27, 2009
Varna, Bulgari
Search for core-collapse supernovae using the MiniBooNE neutrino detector
We present a search for core-collapse supernovae in the Milky Way galaxy, using the MiniBooNE neutrino detector. No evidence is found for core-collapse supernovae occurring in our Galaxy in the period from December 14, 2004 to July 31, 2008, corresponding to 98% live time for collection. We set a limit on the core-collapse supernova rate out to a distance of 13.4 kpc to be less than 0.69 supernovae per year at 90% C. L.We acknowledge the support of Fermilab, the Department of Energy, and the National Science Foundation. We are grateful to John Beacom for his valuable insight and advice. We thank Alessandro Mirizzi, Georg G. Raffelt, and Pasquale D. Serpico for providing the probability distribution for the Milky Way.Peer reviewe
Updated MiniBooNE Neutrino Oscillation Results with Increased Data and New Background Studies
The MiniBooNE experiment at Fermilab reports a total excess of 638.0±132.8 electron-like events (4.8σ) from a data sample corresponding to 18.75×1020 protons-on-target in neutrino mode, which is a 46% increase in the data sample with respect to previously published results, and 11.27 × 1020 protons-on-target in antineutrino mode. The additional statistics allow several studies to address questions on the source of the excess. First, we provide two-dimensional plots in visible energy and cosine of the angle of the outgoing lepton, which can provide valuable input to models for the event excess. Second, we test whether the excess may arise from photons that enter the detector from external events or photons exiting the detector from π0 decays in two model independent ways. Beam timing information shows that almost all of the excess is in time with neutrinos that interact in the detector. The radius distribution shows that the excess is distributed throughout the volume, while tighter cuts on the fiducal volume increase the significance of the excess. We conclude that models of the event excess based on entering and exiting photons are disfavored
MiniBooNE and MicroBooNE Joint Fit to a 3+1 Sterile Neutrino Scenario
This letter presents the results from the MiniBooNE experiment within a full "3+1" scenario where one sterile neutrino is introduced to the three-active-neutrino picture. In addition to electron-neutrino appearance at short-baselines, this scenario also allows for disappearance of the muon-neutrino and electron-neutrino fluxes in the Booster Neutrino Beam, which is shared by the MicroBooNE experiment. We present the 3+1 fit to the MiniBooNE electron-(anti)neutrino and muon-(anti)neutrino data alone, and in combination with the MicroBooNE electron-neutrino CCQE data. The best-fit parameters of this joint fit are eV, , , and . Comparing the no-oscillation scenario to the 3+1 model, the data prefer the 3+1 model with a
MiniBooNE Data Releases
The MiniBooNE experiment has provided data releases for most publications. Occasionally it is necessary to move data release pages. This document provides a single point of reference that will be updated by the collaboration to point to the present location of the MiniBooNE data releases
Detecting sterile neutrinos with KATRIN like experiments
A sterile neutrino with mass in the eV range, mixing with the electron
antineutrino, is allowed and possibly even preferred by cosmology and
oscillation experiments. If such eV-mass neutrinos exist they provide a much
better target for direct detection in beta decay experiments than the active
neutrinos which are expected to have sub-eV masses. Their relatively high mass
would allow for an easy separation from the primary decay signal in experiments
such as KATRIN.Comment: 23 pages, 7 figures. References & Figures updated. Text reviewed and
revised. Accepted for publication JCA
Explaining LSND by a decaying sterile neutrino
We propose an explanation of the LSND evidence for electron antineutrino
appearance based on neutrino decay. We introduce a heavy neutrino, which is
produced in pion and muon decays because of a small mixing with muon neutrinos,
and then decays into a scalar particle and a light neutrino, predominantly of
the electron type. We require values of few eV, being the
neutrino--scalar coupling and the heavy neutrino mass, e.g. in the
range from 1 keV to 1 MeV and . Performing a fit to
the LSND data as well as all relevant null-result experiments, we show that all
data can be explained within this decay scenario. In the minimal version of the
decay model, we predict a signal in the upcoming MiniBooNE experiment
corresponding to a transition probability of the same order as seen in LSND. In
addition, we show that extending our model to two nearly degenerate heavy
neutrinos it is possible to introduce CP violation in the decay, which can lead
to a suppression of the signal in MiniBooNE running in the neutrino mode. We
briefly discuss signals in future neutrino oscillation experiments, we show
that our scenario is compatible with bounds from laboratory experiments, and we
comment on implications in astrophysics and cosmology.Comment: 23 pages, 5 figures, minor improvements, matches published versio