4,268 research outputs found

    The proton structure function F2 in the resonance region

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    Unique measurement of the proton structure function F2 in a wide two-dimensional region of x and Q**2 has been reported. The accessible kinematics covers entire resonance region up to W=2.5 GeV in the Q**2 interval from 0.1 to 4.5 GeV**2. Obtained data allowed for the first time an evaluation of moments of the structure function F2 directly from experimental data as well as an intensive study of the Bloom-Gilman duality phenomenon.Comment: 6 pages, 4 figures, Proceedings of GDH2002 Conference, 3-6 July 2002, Genova, Italy, to be published in World Scientifi

    SCINTILLA A European project for the development of scintillation detectors and new technologies for nuclear security

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    Europe monitors transits using radiation detectors to prevent illicit trafficking of nuclear materials. The SCINTILLA project aims to develop a toolbox of innovative technologies designed to address different usage cases. This article will review the scope, approach, results of the first benchmark campaign and future plans of the SCINTILLA project.Comment: To appear on the Proceedings of the 13th ICATPP Conference on Astroparticle, Particle, Space Physics and Detectors for Physics Applications, Villa Olmo (Como, Italy), 23--27 October, 2013, to be published by World Scientific (Singapore

    P-wave pi pi amplitude from dispersion relations

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    We solve the dispersion relation for the P-wave pi pi amplitude.We discuss the role of the left hand cut vs Castillejo-Dalitz-Dyson (CDD), pole contribution and compare the solution with a generic quark model description. We review the the generic properties of analytical partial wave scattering and production amplitudes and discuses their applicability and fits of experimental data.Comment: 10 pages, 7 figures, typos corrected, reference adde

    Le imprese femminili in Italia: i risultati di un'indagine esplorativa

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    Entrepreneurship has usually been considered a male-dominated activity. In 2012, however, 224mout of 400mentrepreneurs worldwide were women (GEM 2012).Female entrepreneurship therefore clearly represents an important component of the business sector at global level. To date, however, the scope of research on such a relevant topic is still confined to the US and Anglo-Saxon countries. Also, academic research on Italian female entrepreneurship is very limited, despite Italy has the highest number of female-owned firms in Europe (Eurostat, 2013). This paper thus contributes to fill this research gap by investigating the characteristics, the main problems and motivations of 310 Italian female-owned firms

    Photoproduction of the ω\omega meson on the proton at large momentum transfer

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    The differential cross section, dσ/dtd\sigma/dt for ω\omega meson exclusive photoproduction on the proton above the resonance region (2.6<W<2.92.6<W<2.9 GeV) was measured up to a momentum transfer −t=5-t = 5 GeV2^2 using the CLAS detector at Jefferson Laboratory. The ω\omega channel was identified by detecting a proton and π+\pi^+ in the final state and using the missing mass technique. While the low momentum transfer region shows the typical diffractive pattern expected from Pomeron and Reggeon exchange, at large −t-t the differential cross section has a flat behavior. This feature can be explained by introducing quark interchange processes in addition to the QCD-inspired two-gluon exchange.Comment: 5 pages, 5 figure

    Attenuating surface gravity waves with mechanical metamaterials

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    4noMetamaterials and photonic/phononic crystals have been successfully developed in recent years to achieve advanced wave manipulation and control, both in electromagnetism and mechanics. However, the underlying concepts are yet to be fully applied to the field of fluid dynamics and water waves. Here, we present an example of the interaction of surface gravity waves with a mechanical metamaterial, i.e., periodic underwater oscillating resonators. In particular, we study a device composed of an array of periodic submerged harmonic oscillators whose objective is to absorb wave energy and dissipate it inside the fluid in the form of heat. The study is performed using a state-of-the-art direct numerical simulation of the Navier-Stokes equation in its two-dimensional form with free boundary and moving bodies. We use a volume of fluid interface technique for tracking the surface and an immersed boundary method for the fluid-structure interaction. We first study the interaction of a monochromatic wave with a single oscillator and then add up to four resonators coupled only fluid-mechanically. We study the efficiency of the device in terms of the total energy dissipation and find that by adding resonators, the dissipation increases in a nontrivial way. As expected, a large energy attenuation is achieved when the wave and resonators are characterized by similar frequencies. As the number of resonators is increased, the range of attenuated frequencies also increases. The concept and results presented herein are of relevance for coastal protection applications.openpartially_openembargoed_20220426De Vita F.; De Lillo F.; Bosia F.; Onorato M.De Vita, F.; De Lillo, F.; Bosia, F.; Onorato, M
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