67 research outputs found
Modelling CC neutrino cross sections in the few GeV energy region
Selected problems in modelling neutrino-nucleon and -nuclei cross sections in
the neutrino energy region of the few GeV are reviewed.Comment: Presented by J.T. Sobczyk at the Cracow Epiphany Conference on
Neutrinos and Dark Matter, Jan. 5-8, 2006, Cracow, Polan
Four Momentum Transfer Discrepancy in the Charged Current Production in the MiniBooNE: Data vs. Theory
The MiniBooNE experiment has collected what is currently the world's largest
sample of neutrino muon charged current single charged pion interactions,
roughly 46,000 events. The purity of the CC1pi+ sample is 87% making this the
purest event sample observed in the MiniBooNE detector. The average energy of
neutrinos producing CC1pi+ interactions in MiniBooNE is about 1 GeV, therefore
the study of these events can provide insight into both resonant and coherent
pion production processes. In this talk, we will discuss the long-standing
discrepancy in four-momentum transfer observed between CC1pi+ data and existing
predictions. Several attempts to address this problem will be presented.
Specifically, the Rein-Sehgal model has been extended to include muon mass
terms for both resonant [Kuzmin et al. and Berger and Sehgal] and coherent
production. Using calculations from Graczyk and Sobczyk paper, an updated form
for the vector form factor [Lalakulich et al.] has also been adopted. The
results of this improved description of CC1pi+ production will be compared to
the high statistics MiniBooNE CC1pi+ data and several existing parametrisations
of the axial vector form factor.Comment: Presented at 6th International Workshop on Neutrino-Nucleus
Interactions in the Few-GeV Region (NUINT 2009), Sitges, Barcelona, Spain,
18-22 May 2009. Submitted to AIP Conf.Pro
Measurement of the Charged Current Production to Quasi-elastic Scattering Cross Section
Using high statistics samples of charged current interactions, MiniBooNE
reports a model independent measurement of the single charged pion production
to quasi-elastic cross section ratio on mineral oil without corrections for
pion re-interactions in the target nucleus. The result is provided as a
function of neutrino energy in the range 0.4 GeV < E < 2.4 GeV with 11%
precision in the region of highest statistics.Comment: 4 pages, 1 figure, presented at the "Sixth International Workshop on
Neutrino-Nucleus Interactions in the Few-GeV Region (NuInt 2009)
A 1.5D model of a complex geometry laboratory scale fuidized bed clc equipment
The awareness of the climate changes has resulted in the development of new technologies allowing to increase the effectiveness and to lower the costs of CO2 separation from the flue gas. One of the most promised combustion technology of fossil fuels is Chemical Looping Combustion (CLC). The technology is considered to be one of the cheapest techniques for CO2 capture (1). Since it is still an emerging technology and the complexity of processes are still not sufficiently recognized, the development of a simple model of CLC equipment is of practical significance.
The paper presents a 1.5D model of the laboratory-scale fluidized bed CLC equipment for Innovative Idea for Combustion of Solid Fuels via Chemical Looping Technology – NewLoop. The idea combines two technologies making them complementary: Chemical looping with Oxygen Uncoupling (CLOU) and In-situ Gasification Chemical Looping (iG-CLC). Experimental studies, calculations and model validation were performed for the CLC unit (Fig. 1). The unit constitutes two cycles: the main cycle and internal cycle with Air Reactor (AR) and Fuel Reactor (FR). Smooth glass microspheres with the Sauter mean diameter of particles of 141 µm and the density of 2450 kg/m3 were used during the investigation. Since the model is in the development stage the study was conducted for the cold tests at which the unit operated stably and smoothly. The model is performed by the use of Comprehensive Simulator of Fluidized and Moving Bed equipment (CeSFaMB). The CeSFaMB has its first successful version completed in 1987. Since then, various versions have been developed and validated for a wide range of cases (2). The first operational results with this CLC unit, i.e. fluidization dynamics are discussed, since the geometry of the system is rather complex. Pressure drops, void fractions, bubble diameter and rising velocity are determined. The results show good agreement between calculated and experimental parameters. On the matter of fluidization dynamics, CeSFaMB produces the parameters as function of vertical coordinate. As an example, the void fractions as well as bubble diameter and rising velocity in the dense region of the Air Reactor are illustrated in Fig 2.
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Study on cosmogenic activation above ground for the DarkSide-20k project
The activation of materials due to the exposure to cosmic rays may become an important background source for experiments investigating rare event phenomena. DarkSide-20k is a direct detection experiment for galactic dark matter particles, using a two-phase liquid argon time projection chamber filled with 49.7 tonnes (active mass) of Underground Argon (UAr) depleted in 39Ar. Here, the cosmogenic activity of relevant long-lived radioisotopes induced in the argon and other massive components of the set-up has been estimated; production of 120 t of radiopure UAr is foreseen. The expected exposure above ground and production rates, either measured or calculated, have been considered. From the simulated counting rates in the detector due to cosmogenic isotopes, it is concluded that activation in copper and stainless steel is not problematic. Activation of titanium, considered in early designs but not used in the final design, is discussed. The activity of 39Ar induced during extraction, purification and transport on surface, in baseline conditions, is evaluated to be 2.8% of the activity measured in UAr from the same source, and thus considered acceptable. Other products in the UAr such as 37Ar and 3H are shown to not be relevant due to short half-life and assumed purification methods
Novel Approach for Evaluating Detector-Related Uncertainties in a LArTPC Using MicroBooNE Data
Primary challenges for current and future precision neutrino experiments using liquid argon time projection chambers (LArTPCs) include understanding detector effects and quantifying the associated systematic uncertainties. This paper presents a novel technique for assessing and propagating LArTPC detector-related systematic uncertainties. The technique makes modifications to simulation waveforms based on a parameterization of observed differences in ionization signals from the TPC between data and simulation, while remaining insensitive to the details of the detector model. The modifications are then used to quantify the systematic differences in low- and high-level reconstructed quantities. This approach could be applied to future LArTPC detectors, such as those used in SBN and DUNE
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
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