Search results for "31"
showing 10 items of 4401 documents
Combination of Searches for Invisible Higgs Boson Decays with the ATLAS Experiment
2019
Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H → invisible decays where H is produced according to the standard model via vector boson fusion, Z(ℓℓ)H, and W/Z(had)H, all performed with the ATLAS detector using 36.1 fb⁻¹ of pp collisions at a center-of-mass energy of √s = 13 TeV at the LHC. In combination with the results at √s = 7 and 8 TeV, an exclusion limit on the H → invisible branching ratio of 0.26(0.17-0.05+0.07) at 95% confidence level is observed (expected).
Efficient excitation of dielectric-loaded surface plasmon-polariton waveguide modes at telecommunication wavelengths
2008
International audience; The excitation of surface plasmon-polariton (SPP) waveguide modes in subwavelength dielectric ridges deposited on a thin gold film has been characterized and optimized at telecommunication wavelengths. The experimental data on the electromagnetic mode structure obtained using scanning near-field optical microscopy have been directly compared to full vectorial three-dimensional finite element method simulations. Two excitation geometries have been investigated where SPPs are excited outside or inside the dielectric tapered region adjoint to the waveguide. The dependence of the efficiency of the SPP guided mode excitation on the taper opening angle has been measured an…
Analysis of climatic data and forecast indices for human fascioliasis at very high altitude
1999
Human infection with Fasciola hepatica has recently been recognized as an important health problem worldwide, and particularly at very high altitudes in South America. The highest prevalences and intensities of human fascioliasis known are those of the northern Bolivian Altiplano, where infected Lymnaea truncatula occur at altitudes of 3800-4100 m. In the present study, the climatic data for this area of the Altiplano, which differ markedly from those of endemic areas in the lowlands, were analysed. There is no marked seasonality in temperature but there are large variations in temperature within a daily, 24-h period. Rainfall is seasonal, with a long dry season, coinciding with the lowest …
Resolution of the ATLAS muon spectrometer monitored drift tubes in LHC Run 2
2019
The momentum measurement capability of the ATLAS muon spectrometer relies fundamentally on the intrinsic single-hit spatial resolution of the monitored drift tube precision tracking chambers. Optimal resolution is achieved with a dedicated calibration program that addresses the specific operating conditions of the 354 000 high-pressure drift tubes in the spectrometer. The calibrations consist of a set of timing offsets and drift time to drift distance transfer relations, and result in chamber resolution functions. This paper describes novel algorithms to obtain precision calibrations from data collected by ATLAS in LHC Run 2 and from a gas monitoring chamber, deployed in a dedicated gas fac…
Magnetic field effects on human body of wireless chargers for E-bikes
2017
For the electric vehicles battery charging, the wireless power transmission is increasingly representing an innovative solution. The inductive power transfer is the standard technology of wireless charging: the energy transfer occurs between two magnetically coupled coils. Although this battery charging system is especially convenient for E-bikes, the physiological effects of the related magnetic fields shall be estimated and taken into account. In this paper, a 200 W prototype of wireless battery charger for E-bikes is proposed and described. Moreover, various measurements of the surrounding magnetic field are carried out to evaluate the actual physiological compatibility of the system.
L’accertamento del trasferimento d’azienda in caso di cambio di appalto nel rito “Fornero”
2021
Con la sentenza n. 2315/2020 la Suprema Corte ha affermato il principio che l’accertamento dell’anzianità di servizio conseguente ad un trasferimento d’azienda può essere affrontato nell’ambito del rito speciale di impugnazione del licenziamento introdotto dalla L. n. 92/2012. Nella decisione in commento la Corte ha altresì modo di dare continuità all’orientamento per cui la fattispecie traslativa si perfeziona anche in presenza di un mero passaggio di personale in forza di obbligo contrattuale o di legge. Infatti se in un determinato appalto di servizi un imprenditore subentra ad un altro e ne acquisisce il personale e i beni strumentali organizzati (cioè l’azienda), la fattispecie no…
Children’s art: Work or play? Preschoolers considering the economic questions of their theatre performance
2011
During their theatre project, a group of 6-year-old children tried to pursue the role of active actors, decision-makers and producers. For them their theatrical activity was viewed as work, despite the fact that adults tend to count it as play. Children were also eager to earn from their performance. Money was a sign of appreciation and status, and it determined for its part children’s position as genuine actors in an artistic project. The article considers whether some of children’s activity could be understood as work.
Experimental determination of mode I fracture parameters in orthotropic materials by means of Digital Image Correlation
2020
Abstract The mode I fracture parameters for an orthotropic body are directly calculated from full-field deformation measurements provided by Digital Image Correlation (DIC). Three complementary and direct approaches are evaluated and compared: (i) the determination of the Stress Intensity Factor (SIF) by fitting the displacement field using the analytical expression proposed by Lekhnitskii; (ii) the determination of the J-Integral by using the Energy Domain Integral (EDI) formulation on the raw DIC data; and (iii) the calculation of the J-Integral using the EDI approach on the displacement data fitted using Lekhnitskii’s formulation. A comparative experimental study is performed by testing …
On the mechanisms involved in the tensile strength of a dissimilar Ti6Al4V/316L laser welded assembly
2021
International audience; The aim of the present work is to analyze the thermomechanical behavior of dissimilar laser seams by means of FE modeling. The case of a Ti6Al4V/316L assembly with vanadium insert was considered. Effective mechanical properties of the main materials and cords were first estimated from NHT measurements. Modeling of the double pass laser welding process was performed first by considering shrinking of the two weld seams during manufacturing, to get the residual stress state in the welded assembly. Modeling of the tensile test was performed in a second step to study the assembly behavior during loading. In these modeling results, the mesh was the cross-section of the mic…
Different Space Charge Behavior of Materials Used in AC and DC Systems
2017
The aim of the present work is to evaluate the behavior, from the space charge accumulation phenomenon point of view, of three different XLPE specimens used as insulation materials in high voltage systems. Considering that under DC stress the charge accumulation is more relevant as compared to the AC case, in the specimens for DC applications additives are typically added. In this work, three different specimens are analyzed. One is a free additive sample used conventionally under AC stress and two others include different additives that are used under DC stress. In order to measure the space charge accumulation, the Pulsed Electro Acoustic (PEA) method has been employed. For each sample, t…