37 research outputs found

    Dark gravitomagnetism with LISA and gravitational waves space detectors

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    We present here the proposal to use the LISA interferometer for detecting the gravito- magnetic field due to the rotation of the Milky Way, including the contribution given by the dark matter halo. The galactic signal would be superposed to the gravitomagnetic field of the Sun. The technique to be used is based on the asymmetric propagation of light along the closed contour of the space interferometer (Sagnac-like approach). Both principle and practical aspects of the proposed experiment are discussed. The strategy for disentangling the sought for signal from the kinematic terms due to proper rotation and orbital motion is based on the time modulation of the time of flight asymmetry. Such modulation will be originated by the annual oscillation of the plane of the interfer- ometer with respect to the galactic plane. Also the effect of the gravitomagnetic field on the polarization of the electromagnetic signals is presented as an in principle detectable phenomenon

    Enhanced Lightweight Design : First Results of the FP7 Project ENLIGHT

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    © 2016 The Authors. Published by Elsevier B.V. The European Green Vehicle project ENLIGHT aims to advance highly innovative lightweight material technologies for application in structural vehicle parts of future volume produced Electric Vehicles (EVs) along four axes: performance, manufacturability, cost effectiveness and lifecycle footprint. The main target is to develop viable and sustainable solutions for medium production volume up to 50.000 EVs destined to reach the market in the next 8-12 years. The specific objectives of the ENLIGHT project are on holistic and integrated conceptual design and manufacturing concerning how the technologies and materials addressed can be combined into a representative medium-volume EV. The solutions will be demonstrated in five modules: a front module and central floor module, a front door, a sub-frame and suspension system as well as a cross-car beam. In this paper, a summary of the major results obtained up to the 3rd project year will be presented. ispartof: pages:1031-1040 ispartof: Transportation Research Procedia vol:14 pages:1031-1040 ispartof: 6th Transport Research Arena TRA2016 location:Warsaw, Poland date:18 Apr - 21 Apr 2016 status: publishe

    Effect of the iodine atom position on the phosphorescence of BODIPY derivatives: a combined computational and experimental study

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    A new BODIPY derivative (o-I-BDP) containing an iodine atom in the ortho position of the meso-linked phenyl group was prepared. Photophysical and electrochemical properties of the molecule were compared to previously reported iodo BODIPY derivatives, as well as to the non-iodinated analog. While in the case of derivatives featuring iodine substituents in the BODIPY core, efficient population of the triplet state is accompanied by a substantial positive shift of the reduction potential compared to pristine BODIPY, o-I-BDP displays phosphorescence and simultaneously maintains the electrochemical properties of unsubstituted BODIPYs. A theoretical investigation was settled to analyze results and rationalize the influence of iodine position on electronic and photophysical properties, with the purpose of preparing a fully organic phosphorescent BODIPY derivative. TD-DFT and spin-orbit coupling calculations shed light on the subtle effects played by the introduction of iodine atom in different positions of BODIPY

    Stochastic conversions of TeV photons into axion-like particles in extragalactic magnetic fields

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    Very-high energy photons emitted by distant cosmic sources are absorbed on the extragalactic background light (EBL) during their propagation. This effect can be characterized in terms of a photon transfer function at Earth. The presence of extragalactic magnetic fields could also induce conversions between very high-energy photons and hypothetical axion-like particles (ALPs). The turbulent structure of the extragalactic magnetic fields would produce a stochastic behaviour in these conversions, leading to a statistical distribution of the photon transfer functions for the different realizations of the random magnetic fields. To characterize this effect, we derive new equations to calculate the mean and the variance of this distribution. We find that, in presence of ALP conversions, the photon transfer functions on different lines of sight could have relevant deviations with respect to the mean value, producing both an enhancement or a suppression in the observable photon flux with respect to the expectations with only absorption. As a consequence, the most striking signature of the mixing with ALPs would be a reconstructed EBL density from TeV photon observations which appears to vary over different directions of the sky: consistent with standard expectations in some regions, but inconsistent in others.Comment: v2: 22 pages, 5 eps figures. Minor changes. A reference added. Matches the version published on JCA

    Sub-Femto- g Free Fall for Space-Based Gravitational Wave Observatories: LISA Pathfinder Results

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    We report the first results of the LISA Pathfinder in-flight experiment. The results demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with a relative acceleration noise with a square root of the power spectral density of 5.2±0.1  fm s−2/Hz, or (0.54±0.01)×10−15  g/Hz, with g the standard gravity, for frequencies between 0.7 and 20 mHz. This value is lower than the LISA Pathfinder requirement by more than a factor 5 and within a factor 1.25 of the requirement for the LISA mission, and is compatible with Brownian noise from viscous damping due to the residual gas surrounding the test masses. Above 60 mHz the acceleration noise is dominated by interferometer displacement readout noise at a level of (34.8±0.3)  fm/Hz, about 2 orders of magnitude better than requirements. At f≤0.5  mHz we observe a low-frequency tail that stays below 12  fm s−2/Hz down to 0.1 mHz. This performance would allow for a space-based gravitational wave observatory with a sensitivity close to what was originally foreseen for LISA.CNES 1316634/CNRS 103747UnivEarthS Labex program/ANR-10-LABX-0023UnivEarthS Labex program/ANR-11-IDEX-0005-02DLRFederal Ministry for Economic Affairs and Energy/FKZ 50OQ0501Federal Ministry for Economic Affairs and Energy/FKZ 50OQ1601Agenzia Spaziale ItalianaInstituto Nazionale di Fisica NucleareAYA2010-15709 (MICINN)ESP2013-47637-P (MINECO)ESP2015-67234-P (MINECO)Fundacion General CSICSwiss Space Office (SSO)Swiss National Science FoundationUnited Kingdom Space Agency (UKSA)University of GlasgowUniversity of BirminghamImperial CollegeScottish Universities Physics Alliance (SUPA)U.S. National Aeronautics and Space Administration (NASA

    Epidemiology and clinical course of severe acute respiratory syndrome coronavirus 2 infection in cancer patients in the Veneto Oncology Network: The Rete Oncologica Veneta covID19 study

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    Introduction: Coronavirus disease 2019 (COVID-19) pandemic started in Italy with clusters identified in Northern Italy. The Veneto Oncology Network (Rete Oncologica Veneta) licenced dedicated guidelines to ensure proper care minimising the risk of infection in patients with cancer. Rete Oncologica Veneta covID19 (ROVID) is a regional registry aimed at describing epidemiology and clinical course of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with cancer. Materials and methods: Patients with cancer diagnosis and documented SARS-CoV-2 infection are eligible. Data on cancer diagnosis, comorbidities, anticancer treatments, as well as details on SARS-CoV-2 infection (hospitalisation, treatments, fate of the infection), have been recorded. Logistic regression analysis was applied to calculate the association between clinical/laboratory variables and death from any cause. Results: One hundred seventy patients have been enrolled. The median age at time of the SARS-CoV infection was 70 years (25-92). The most common cancer type was breast cancer (n = 40). The majority of the patients had stage IV disease. Half of the patients had two or more comorbidities. The majority of the patients (78%) presented with COVID-19 symptoms. More than 77% of the patients were hospitalized and 6% were admitted to intensive care units. Overall, 104 patients have documented resolution of the infection. Fifty-seven patients (33%) have died. In 29 cases (17%), the cause of death was directly correlated to SARS-CoV-2 infection. Factors significantly correlated with the risk of death were the following: Eastern Cooperative Oncology Group performance status (PS), age, presence of two or more comorbidities, presence of dyspnoea, COVID-19 phenotype ≥ 3, hospitalisation, intensive care unit admission, neutrophil/lymphocyte ratio and thrombocytopenia. Conclusions: The mortality rate reported in this confirms the frailty of this population. These data reinforce the need to protect patients with cancer from SARS-CoV-2 infection

    Calibrating LISA Pathfinder raw data into femto-g differential accelerometry

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    LISA Pathfinder is an in-flight test of the local sources of acceleration noise in LISA. The acceleration noise level in LISA Pathfinder is measured by the residual differential acceleration Δg between the two test masses once the coupling to the spacecraft motion has been removed. The full process from raw data to Δg passes through a series of calibration experiments and different data elaboration procedure which are thoroughly used during the mission and represent the baseline for any other further investigation

    Influence of temperature on in-plane and out-of-plane mechanical behaviour of GFRP composite

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    In this work, the challenges in forming of glass-fibre reinforced PA6, from experimental material characterization and parameter identification to numerical modelling using Finite Element Analyses (FEA) is reviewed and results are presented. Mechanical in-plane behaviour is characterized by tensile and bias extension tests. Out-of-plane characteristics are determined using the cantilever test. The constitutive model is set-up using LS-DYNA™, in which the fibre and matrix properties are considered separately. Therefore seperate tensile experiments with unreinforced PA6 are performed. FEA is used to model the tensile and cantilever tests in which the strain-stress curves, influence of displacement on shearing angle and different approaches in modelling the bending stiffness are compared. The advantages and drawbacks of the model are shown and discussed. It is shown that the conducted experiments can be reproduced by using the implemented material model and reasonably good results are achieved.ISSN:1742-6588ISSN:1742-659

    Detecting gravitomagnetism with space-based gravitational wave observatories

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    We discuss the idea of a measurement that, making use of data from space interferometers, could detect the gravito-magnetic field generated by the rotation of the Milky Way, including the possible contribution of the dark matter halo. The galactic signal would be superposed to the gravito-magnetic field of the Sun. The proposed technique is based on the asymmetric propagation of light along the closed contour of the space interferometer, in a Sagnac-like approach. We discuss the principles of detection as well as some practical aspects of the proposed experiment using, as a case study, LISA, the most mature project to date. Both gravito-magnetic signals will be modulated thanks to the annual oscillation of the plane of the interferometer with respect to the galactic plane and to the spin axis of the Sun. Although larger than the detector intrinsic noise, these signals will be superposed to a much larger kinematic modulation due to orbital motion, making them very hard to be observed. We also mention a second phenomenon, where the gravito-magnetic field rotates the polarization of the propagating electromagnetic beams: the effect will be present in LISA, although exceedingly small and out of reach of present technology

    Affordable Multi-Material Lightweight Design - Selected Results of the H2020 Project ALLIANCE: Paper presented at the Transport Research Arena (TRA), 27–30 April 2020, Helsinki, Finland

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    In the last years, the research activities in the field of lightweighting have been advancing rapidly. The introduction of innovative materials and manufacturing technologies have allowed significant weight reduction. Despite this, novel technologies and materials have not reached a wide distribution. The reasons for this are mainly high production costs and environmental impacts of manufacturing that do not compensate benefits during operation. The paper will discuss selected final results of the H2020 project AffordabLe LIghtweight Automobiles AlliaNCE (ALLIANCE, www.lightweight-alliance.eu) which has the goal of developing novel advanced automotive materials and production technologies, aiming at an average 30% weight reduction over 100k units/year, at costs of < 3 â¬/kg-saved. An o verlook of the realized demonstrators will be given and the applied new materials and manufacturing technologies discussed. A special focus will be put on how the different concepts, materials and manufacturing technologies have been evaluated regarding GWP and costs
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