405 research outputs found
First Measurement of Monoenergetic Muon Neutrino Charged Current Interactions
We report the first measurement of monoenergetic muon neutrino charged
current interactions. MiniBooNE has isolated 236 MeV muon neutrino events
originating from charged kaon decay at rest ()
at the NuMI beamline absorber. These signal -carbon events are
distinguished from primarily pion decay in flight and
backgrounds produced at the target station and decay pipe
using their arrival time and reconstructed muon energy. The significance of the
signal observation is at the 3.9 level. The muon kinetic energy,
neutrino-nucleus energy transfer (), and total cross
section for these events is extracted. This result is the first known-energy,
weak-interaction-only probe of the nucleus to yield a measurement of
using neutrinos, a quantity thus far only accessible through electron
scattering.Comment: 6 pages, 4 figure
A Search for Electron Antineutrino Appearance at the 1 Scale
The MiniBooNE Collaboration reports initial results from a search for
oscillations. A signal-blind analysis was
performed using a data sample corresponding to protons on
target. The data are consistent with background prediction across the full
range of neutrino energy reconstructed assuming quasielastic scattering, MeV: 144 electron-like events have been observed in this
energy range, compared to an expectation of events. No
significant excess of events has been observed, both at low energy, 200-475
MeV, and at high energy, 475-1250 MeV. The data are inconclusive with respect
to antineutrino oscillations suggested by data from the Liquid Scintillator
Neutrino Detector at Los Alamos National Laboratory.Comment: 5 pages, 3 figures, 2 table
Measurement of the neutrino component of an anti-neutrino beam observed by a non-magnetized detector
Two independent methods are employed to measure the neutrino flux of the
anti-neutrino-mode beam observed by the MiniBooNE detector. The first method
compares data to simulated event rates in a high purity \numu induced
charged-current single \pip (CC1\pip) sample while the second exploits the
difference between the angular distributions of muons created in \numu and
\numub charged-current quasi-elastic (CCQE) interactions. The results from
both analyses indicate the prediction of the neutrino flux component of the
pre-dominately anti-neutrino beam is over-estimated - the CC1\pip analysis
indicates the predicted \numu flux should be scaled by , while
the CCQE angular fit yields . The energy spectrum of the flux
prediction is checked by repeating the analyses in bins of reconstructed
neutrino energy, and the results show that the spectral shape is well modeled.
These analyses are a demonstration of techniques for measuring the neutrino
contamination of anti-neutrino beams observed by future non-magnetized
detectors.Comment: 15 pages, 7 figures, published in Physical Review D, latest version
reflects changes from referee comment
The Cytoplasmic Location of Chicken Mx Is Not the Determining Factor for Its Lack of Antiviral Activity
Chicken Mx belongs to the Mx family of interferon-induced dynamin-like GTPases, which in some species possess potent antiviral properties. Conflicting data exist for the antiviral capability of chicken Mx. Reports of anti-influenza activity of alleles encoding an Asn631 polymorphism have not been supported by subsequent studies. The normal cytoplasmic localisation of chicken Mx may influence its antiviral capacity. Here we report further studies to determine the antiviral potential of chicken Mx against Newcastle disease virus (NDV), an economically important cytoplasmic RNA virus of chickens, and Thogoto virus, an orthomyxovirus known to be exquisitely sensitive to the cytoplasmic MxA protein from humans. We also report the consequences of re-locating chicken Mx to the nucleus.Chicken Mx was tested in virus infection assays using NDV. Neither the Asn631 nor Ser631 Mx alleles (when transfected into 293T cells) showed inhibition of virus-directed gene expression when the cells were subsequently infected with NDV. Human MxA however did show significant inhibition of NDV-directed gene expression. Chicken Mx failed to inhibit a Thogoto virus (THOV) minireplicon system in which the cytoplasmic human MxA protein showed potent and specific inhibition. Relocalisation of chicken Mx to the nucleus was achieved by inserting the Simian Virus 40 large T antigen nuclear localisation sequence (SV40 NLS) at the N-terminus of chicken Mx. Nuclear re-localised chicken Mx did not inhibit influenza (A/PR/8/34) gene expression during virus infection in cell culture or influenza polymerase activity in A/PR/8/34 or A/Turkey/50-92/91 minireplicon systems.The chicken Mx protein (Asn631) lacks inhibitory effects against THOV and NDV, and is unable to suppress influenza replication when artificially re-localised to the cell nucleus. Thus, the natural cytoplasmic localisation of the chicken Mx protein does not account for its lack of antiviral activity
Overview on the phenomenon of two-qubit entanglement revivals in classical environments
The occurrence of revivals of quantum entanglement between separated open
quantum systems has been shown not only for dissipative non-Markovian quantum
environments but also for classical environments in absence of back-action.
While the phenomenon is well understood in the first case, the possibility to
retrieve entanglement when the composite quantum system is subject to local
classical noise has generated a debate regarding its interpretation. This
dynamical property of open quantum systems assumes an important role in quantum
information theory from both fundamental and practical perspectives. Hybrid
quantum-classical systems are in fact promising candidates to investigate the
interplay among quantum and classical features and to look for possible control
strategies of a quantum system by means of a classical device. Here we present
an overview on this topic, reporting the most recent theoretical and
experimental results about the revivals of entanglement between two qubits
locally interacting with classical environments. We also review and discuss the
interpretations provided so far to explain this phenomenon, suggesting that
they can be cast under a unified viewpoint.Comment: 16 pages, 9 figures. Chapter written for the upcoming book "Lectures
on general quantum correlations and their applications
Light Sterile Neutrinos: A White Paper
This white paper addresses the hypothesis of light sterile neutrinos based on
recent anomalies observed in neutrino experiments and the latest astrophysical
data
Synthesis and characterization of BaTiO3/-Fe2O3 core/shell structure
Multiferroic materials attracted a lot of attention in recent years because of their significant scientific interest and technological applications. The multiferroic core/shell powders have a better connectivity between the phases, resulting in superior dielectric and magneto electric properties. In this study, the influence of preparation condition on structure and properties of BaTiO3/-Fe2O3 core/shell composite materials was examined. The five samples were obtained by varying synthesis conditions, such as synthesized method (co-precipitation and sonochemical method) and pH values of solution. XRD and Raman spectroscopy analyses were performed in order to determine phase composition and structural changes within samples. Morphology modifications were examined by SEM and EDS analyses. Finally, effect of structural and microstructural changes on magnetic and electrical properties was detected and explained
Design and construction of the MicroBooNE Cosmic Ray Tagger system
The MicroBooNE detector utilizes a liquid argon time projection chamber
(LArTPC) with an 85 t active mass to study neutrino interactions along the
Booster Neutrino Beam (BNB) at Fermilab. With a deployment location near ground
level, the detector records many cosmic muon tracks in each beam-related
detector trigger that can be misidentified as signals of interest. To reduce
these cosmogenic backgrounds, we have designed and constructed a TPC-external
Cosmic Ray Tagger (CRT). This sub-system was developed by the Laboratory for
High Energy Physics (LHEP), Albert Einstein center for fundamental physics,
University of Bern. The system utilizes plastic scintillation modules to
provide precise time and position information for TPC-traversing particles.
Successful matching of TPC tracks and CRT data will allow us to reduce
cosmogenic background and better characterize the light collection system and
LArTPC data using cosmic muons. In this paper we describe the design and
installation of the MicroBooNE CRT system and provide an overview of a series
of tests done to verify the proper operation of the system and its components
during installation, commissioning, and physics data-taking
A Deep Neural Network for Pixel-Level Electromagnetic Particle Identification in the MicroBooNE Liquid Argon Time Projection Chamber
We have developed a convolutional neural network (CNN) that can make a
pixel-level prediction of objects in image data recorded by a liquid argon time
projection chamber (LArTPC) for the first time. We describe the network design,
training techniques, and software tools developed to train this network. The
goal of this work is to develop a complete deep neural network based data
reconstruction chain for the MicroBooNE detector. We show the first
demonstration of a network's validity on real LArTPC data using MicroBooNE
collection plane images. The demonstration is performed for stopping muon and a
charged current neutral pion data samples
Ionization Electron Signal Processing in Single Phase LArTPCs II. Data/Simulation Comparison and Performance in MicroBooNE
The single-phase liquid argon time projection chamber (LArTPC) provides a
large amount of detailed information in the form of fine-grained drifted
ionization charge from particle traces. To fully utilize this information, the
deposited charge must be accurately extracted from the raw digitized waveforms
via a robust signal processing chain. Enabled by the ultra-low noise levels
associated with cryogenic electronics in the MicroBooNE detector, the precise
extraction of ionization charge from the induction wire planes in a
single-phase LArTPC is qualitatively demonstrated on MicroBooNE data with event
display images, and quantitatively demonstrated via waveform-level and
track-level metrics. Improved performance of induction plane calorimetry is
demonstrated through the agreement of extracted ionization charge measurements
across different wire planes for various event topologies. In addition to the
comprehensive waveform-level comparison of data and simulation, a calibration
of the cryogenic electronics response is presented and solutions to various
MicroBooNE-specific TPC issues are discussed. This work presents an important
improvement in LArTPC signal processing, the foundation of reconstruction and
therefore physics analyses in MicroBooNE.Comment: 54 pages, 36 figures; the first part of this work can be found at
arXiv:1802.0870
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