Search results for "ARTICLES"

Limits on point-like sources of ultra-high-energy neutrinos with the Pierre Auger Observatory

2019

With the Surface Detector array (SD) of the Pierre Auger Observatory we can detect neutrinos with energy between 1017 eV and 1020 eV from point-like sources across the sky, from close to the Southern Celestial Pole up to 60 in declination, with peak sensitivities at declinations around ∼-53 and ∼+55, and an unmatched sensitivity for arrival directions in the Northern hemisphere. A search has been performed for highly-inclined air showers induced by neutrinos of all flavours with no candidate events found in data taken between 1 Jan 2004 and 31 Aug 2018. Upper limits on the neutrino flux from point-like steady sources have been derived as a function of source declination. An unrivaled sensit…

Use of the directional atherectomy for the treatment of femoro-popliteal lesions in patients with critical lower limb ischemia

2016

Femoro-popliteal PTA for the treatment of critical limb ischemia is frequently associated with unsatisfactory procedural success rates while directional atherectomy (DCA) has improved success rate since claudicant patients undergoing percutaneous treatment of femoro-popliteal obstructive disease. The aim of this prospective study is to evaluate the safety, efficacy and procedural success of DCA, at one year, in the percutaneous treatment of femoro-popliteal obstructive disease in patients with critical limb ischemia.Methods. From March 2012 to March 2013 18 consecutive patients with critical limb ischemia were treated with DCA (Turbohawk/ Covidien-ev3 Endovascular Inc., North Plymouth, Minn…

Predicting needlestick and sharps injuries in nursing students: Development of the SNNIP scale

2020

© 2020 The Authors. Nursing Open published by John Wiley & Sons Ltd. Aim: To develop an instrument to investigate knowledge and predictive factors of needlestick and sharps injuries (NSIs) in nursing students during clinical placements. Design: Instrument development and cross-sectional study for psychometric testing. Methods: A self-administered instrument including demographic data, injury epidemiology and predictive factors of NSIs was developed between October 2018–January 2019. Content validity was assessed by a panel of experts. The instrument's factor structure and discriminant validity were explored using principal components analysis. The STROBE guidelines were followed. Results: E…

Drug delivery systems based on polymeric micro and nanoparticles for the treatment of cystic fibrosis

Estimating QCD uncertainties in Monte Carlo event generators for gamma-ray dark matter searches

2018

Motivated by the recent galactic center gamma-ray excess identified in the Fermi-LAT data, we perform a detailed study of QCD fragmentation uncertainties in the modeling of the energy spectra of gamma-rays from Dark-Matter (DM) annihilation. When Dark-Matter particles annihilate to coloured final states, either directly or via decays such as $W^{(*)}\to q\bar{q}'$, photons are produced from a complex sequence of shower, hadronisation and hadron decays. In phenomenological studies, their energy spectra are typically computed using Monte Carlo event generators. These results have however intrinsic uncertainties due to the specific model used and the choice of model parameters, which are diffi…

Physics reach of the XENON1T dark matter experiment.

2016

The XENON1T experiment is currently in the commissioning phase at the Laboratori Nazionali del Gran Sasso, Italy. In this article we study the experiment's expected sensitivity to the spin-independent WIMP-nucleon interaction cross section, based on Monte Carlo predictions of the electronic and nuclear recoil backgrounds. The total electronic recoil background in $1$ tonne fiducial volume and ($1$, $12$) keV electronic recoil equivalent energy region, before applying any selection to discriminate between electronic and nuclear recoils, is $(1.80 \pm 0.15) \cdot 10^{-4}$ ($\rm{kg} \cdot day \cdot keV)^{-1}$, mainly due to the decay of $^{222}\rm{Rn}$ daughters inside the xenon target. The nu…

Measurement of the cosmic ray proton spectrum from 40 GeV to 100 TeV with the DAMPE satellite

2019

DAMPE satellite has directly measured the cosmic ray proton spectrum from 40 GeV to 100 TeV and revealed a new feature at about 13.6 TeV.

Computational Techniques for the Analysis of Small Signals in High-Statistics Neutrino Oscillation Experiments

2020

The current and upcoming generation of Very Large Volume Neutrino Telescopes – collecting unprecedented quantities of neutrino events – can be used to explore subtle effects in oscillation physics, such as (but not restricted to) the neutrino mass ordering. The sensitivity of an experiment to these effects can be estimated from Monte Carlo simulations. With the high number of events that will be collected, there is a trade-off between the computational expense of running such simulations and the inherent statistical uncertainty in the determined values. In such a scenario, it becomes impractical to produce and use adequately-sized sets of simulated events with traditional methods, such as M…

Measurement of θ13 in Double Chooz using neutron captures on hydrogen with novel background rejection techniques

2016

The Double Chooz collaboration presents a measurement of the neutrino mixing angle θ[subscript 13] using reactor [bar over ν[subscript e]] observed via the inverse beta decay reaction in which the neutron is captured on hydrogen. This measurement is based on 462.72 live days data, approximately twice as much data as in the previous such analysis, collected with a detector positioned at an average distance of 1050 m from two reactor cores. Several novel techniques have been developed to achieve significant reductions of the backgrounds and systematic uncertainties. Accidental coincidences, the dominant background in this analysis, are suppressed by more than an order of magnitude with respec…

Intrinsic backgrounds from Rn and Kr in the XENON100 experiment

2018

In this paper, we describe the XENON100 data analyses used to assess the target-intrinsic background sources radon ([InlineMediaObject not available: see fulltext.]), thoron ([InlineMediaObject not available: see fulltext.]) and krypton ([InlineMediaObject not available: see fulltext.]). We detail the event selections of high-energy alpha particles and decay-specific delayed coincidences. We derive distributions of the individual radionuclides inside the detector and quantify their abundances during the main three science runs of the experiment over a period of ∼4years, from January 2010 to January 2014. We compare our results to external measurements of radon emanation and krypton concentr…