287 research outputs found
A Novel Electrical Method to Measure Wire Tensions for Time Projection Chambers
We present a novel electrical technique to measure the tension of wires in
multi-wire drift chambers. We create alternating electric fields by biasing
adjacent wires on both sides of a test wire with a superposition of positive
and negative DC voltages on an AC signal (). The
resulting oscillations of the wire will display a resonance at its natural
frequency, and the corresponding change of the capacitance will lead to a
measurable current. This scheme is scalable to multiple wires and therefore
enables us to precisely measure the tension of a large number of wires in a
short time. This technique can also be applied at cryogenic temperatures making
it an attractive solution for future large time-projection chambers such as the
DUNE detector. We present the concept, an example implementation and its
performance in a real-world scenario and discuss the limitations of the
sensitivity of the system in terms of voltage and wire length.Comment: 7 pages, 8 figures. Accepted by NIM
Recommended from our members
Calibration of the charge and energy loss per unit length of the MicroBooNE liquid argon time projection chamber using muons and protons
We describe a method used to calibrate the position- and time-dependent response of the MicroBooNE liquid argon time projection chamber anode wires to ionization particle energy loss. The method makes use of crossing cosmic-ray muons to partially correct anode wire signals for multiple effects as a function of time and position, including cross-connected TPC wires, space charge effects, electron attachment to impurities, diffusion, and recombination. The overall energy scale is then determined using fully-contained beam-induced muons originating and stopping in the active region of the detector. Using this method, we obtain an absolute energy scale uncertainty of 2% in data. We use stopping protons to further refine the relation between the measured charge and the energy loss for highly-ionizing particles. This data-driven detector calibration improves both the measurement of total deposited energy and particle identification based on energy loss per unit length as a function of residual range. As an example, the proton selection efficiency is increased by 2% after detector calibration
Recommended from our members
Reconstruction and measurement of (100) MeV energy electromagnetic activity from π0 arrow γγ decays in the MicroBooNE LArTPC
We present results on the reconstruction of electromagnetic (EM) activity from photons produced in charged current νμ interactions with final state π0s. We employ a fully-automated reconstruction chain capable of identifying EM showers of (100) MeV energy, relying on a combination of traditional reconstruction techniques together with novel machine-learning approaches. These studies demonstrate good energy resolution, and good agreement between data and simulation, relying on the reconstructed invariant π0 mass and other photon distributions for validation. The reconstruction techniques developed are applied to a selection of νμ + Ar → μ + π0 + X candidate events to demonstrate the potential for calorimetric separation of photons from electrons and reconstruction of π0 kinematics
Modelling innovative interventions for optimising healthy lifestyle promotion in primary health care: "Prescribe Vida Saludable" phase I research protocol
<p>Abstract</p> <p>Background</p> <p>The adoption of a healthy lifestyle, including physical activity, a balanced diet, a moderate alcohol consumption and abstinence from smoking, are associated with large decreases in the incidence and mortality rates for the most common chronic diseases. That is why primary health care (PHC) services are trying, so far with less success than desirable, to promote healthy lifestyles among patients. The objective of this study is to design and model, under a participative collaboration framework between clinicians and researchers, interventions that are feasible and sustainable for the promotion of healthy lifestyles in PHC.</p> <p>Methods and design</p> <p>Phase I formative research and a quasi-experimental evaluation of the modelling and planning process will be undertaken in eight primary care centres (PCCs) of the Basque Health Service – OSAKIDETZA, of which four centres will be assigned for convenience to the Intervention Group (the others being Controls). Twelve structured study, discussion and consensus sessions supported by reviews of the literature and relevant documents, will be undertaken throughout 12 months. The first four sessions, including a descriptive strategic needs assessment, will lead to the prioritisation of a health promotion aim in each centre. In the remaining eight sessions, collaborative design of intervention strategies, on the basis of a planning process and pilot trials, will be carried out. The impact of the formative process on the practice of healthy lifestyle promotion, attitude towards health promotion and other factors associated with the optimisation of preventive clinical practice will be assessed, through pre- and post-programme evaluations and comparisons of the indicators measured in professionals from the centres assigned to the Intervention or Control Groups.</p> <p>Discussion</p> <p>There are four necessary factors for the outcome to be successful and result in important changes: (1) the commitment of professional and community partners who are involved; (2) their competence for change; (3) the active cooperation and participation of the interdisciplinary partners involved throughout the process of change; and (4) the availability of resources necessary to facilitate the change.</p
First Measurement of Electron Neutrino Scattering Cross Section on Argon
We report the first electron neutrino cross section measurements on argon,
based on data collected by the ArgoNeuT experiment running in the GeV-scale
NuMI beamline at Fermilab. A flux-averaged total and
a lepton angle differential cross section are extracted using 13 and
events identified with fully-automated selection and
reconstruction. We employ electromagnetic-induced shower characterization and
analysis tools developed to identify -like events among
complex interaction topologies present in ArgoNeuT data ( GeV and GeV).
The techniques are widely applicable to searches for electron-flavor appearance
at short- and long-baseline using liquid argon time projection chamber
technology. Notably, the data-driven studies of GeV-scale
interactions presented in this Letter probe an energy
regime relevant for future DUNE oscillation physics.Comment: added acknowledgement
Ulcerogenic Helicobacter pylori Strains Isolated from Children: A Contribution to Get Insight into the Virulence of the Bacteria
Infection with Helicobacter pylori is the major cause for the development of peptic ulcer disease (PUD). In children, with no other etiology for the disease, this rare event occurs shortly after infection. In these young patients, habits of smoking, diet, consumption of alcohol and non-steroid anti-inflammatory drugs and stress, in addition to the genetic susceptibility of the patient, represent a minor influence. Accordingly, the virulence of the implicated H. pylori strain should play a crucial role in the development of PUD. Corroborating this, our in vitro infection assays comparing a pool of five H. pylori strains isolated from children with PUD to a pool of five other pediatric clinical isolates associated with non-ulcer dyspepsia (NUD) showed the greater ability of PUD strains to induce a marked decrease in the viability of gastric cells and to cause severe damage in the cells cytoskeleton as well as an impairment in the production/secretion of mucins. To uncover virulence features, we compared the proteome of these two groups of H. pylori strains. Two-dimensional gel electrophoresis followed by mass-spectrometry allowed us to detect 27 differentially expressed proteins between them. In addition to the presence of genes encoding well established virulence factors, namely cagA, vacAs1, oipA “on” status, homB and jhp562 genes, the pediatric ulcerogenic strains shared a proteome profile characterized by changes in the abundance of: motility-associated proteins, accounting for higher motility; antioxidant proteins, which may confer increased resistance to inflammation; and enzymes involved in key steps in the metabolism of glucose, amino acids and urea, which may be advantageous to face fluctuations of nutrients. In conclusion, the enhanced virulence of the pediatric ulcerogenic H. pylori strains may result from a synergy between their natural ability to better adapt to the hostile human stomach and the expression of the established virulence factors
Measurement of nuclear effects in neutrino-argon interactions using generalized kinematic imbalance variables with the MicroBooNE detector
We present a set of new generalized kinematic imbalance variables that can be measured in neutrino scattering. These variables extend previous measurements of kinematic imbalance on the transverse plane and are more sensitive to modeling of nuclear effects. We demonstrate the enhanced power of these variables using simulation and then use the MicroBooNE detector to measure them for the first time. We report flux-integrated single- and double-differential measurements of charged-current muon neutrino scattering on argon using a topology with one muon and one proton in the final state as a function of these novel kinematic imbalance variables. These measurements allow us to demonstrate that the treatment of charged current quasielastic interactions in genie version 2 is inadequate to describe data. Further, they reveal tensions with more modern generator predictions particularly in regions of phase space where final state interactions are important
- …