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[en] Data collected at the Tevatron proton-antiproton collider are still producing interesting results. Measurements of QCD, top and electroweak quantities are competitive to LHC because of the low center of mass energy, √ s = 1.96 GeV and due to the fact that this is proton-antiproton data. This report describes the CDF measurement of the prompt photon cross section and the determination of the effective leptonic electroweak mixing angle by CDF and D0 experiments. The combination of the two results gives a precise measurement of sin2 θlepeff from which the W mass is inferred by using standard model calculations.
[en] The DarkSide experiment aims to perform a background-free direct search for dark matter with a dual-phase argon TPC. The current phase of the experiment, DarkSide-50, is acquiring data at Laboratori Nazionali del Gran Sasso and produced the most sensitive limit on the WIMP-nucleon cross section ever obtained with a liquid argon target (2.0 × 10-44 cm2 for a WIMP mass of 100 GeV/c2). The future phase of the experiment will be a 20 t fiducial mass detector, designed to reach a sensitivity of ~1 × 10-47 cm2 (at 1 TeV/c2 WIMP mass) with a background-free exposure of 100 ty. Here, this work contains a discussion of the current status of the DarkSide-50 WIMP search and of the results which are more relevant for the construction of the future detector.
[en] The Mu2e experiment at Fermilab will search for coherent, neutrinoless conversion of negative muons into electrons in the field of an aluminum nucleus. The dynamics of such charged lepton flavour violating (CLFV) process is a twobody decay, resulting in a mono-energetic electron with an energy slightly below the muon rest mass. If no events are observed in three years of running, Mu2e will set an upper limit on the ratio between the conversion and the capture rates Rμe of ≤ 6 × 10-17 (@90% C.L.). This will improve the current limit of four order of magnitudes with respect to the previous best experiment. Mu2e complements and extends the current search for μ → eγ decay at MEG as well as the direct searches for new physics at the LHC. Indeed, such a CLFV process probes new physics at a scale inaccessible to direct searches at either present or planned high energy colliders. Observation of a signal will be a clear evidence for new physics beyond the Standard Model. To search for the muon conversion process, a very intense pulsed beam of negative muons (~ 1010 μ/s) is stopped on an aluminum target inside a very long solenoid where the detector is also located. The Mu2e detector is composed of a straw tube tracker and an electromagnetic calorimeter consisting of arrays of CsI crystals. An external veto for cosmic rays is surrounding the detector solenoid. In 2016, Mu2e has passed the final approval stage from DOE and has started its construction phase. Data collection is planned for the end of 2021. Lastly, an overview of the physics motivations for Mu2e, the current status of the experiment and design of the muon beam-line and the detector is presented.
[en] We present the observation of doubly produced J/ψ mesons as an example of processes containing a substantial fraction of double parton scattering. Measurements of the production cross sections for singly and doubly-produced J/ψ mesons were done with the D0 detector at Fermilab in pp̄ collisions at √s = 1.96 TeV with an integrated luminosity of 8.1 fb"−"1. For the first time, the double J/ψ production cross section is separated into two parts: contributions from both single and double parton scattering. Lastly, this separation allowed us to determine the effective cross section σ_e_f_f, a parameter related to the parton spatial density inside the hadron.
[en] This volume contains most of the contributions presented at the Conference 'Mathematical Structures in Quantum Systems and applications', held at the Centro de Ciencias de Benasque 'Pedro Pascual', Benasque (Spain) from 8-14 July 2012. The aim of the Conference was to bring together physicists working on different applications of mathematical methods to quantum systems in order to enable the different communities to become acquainted with other approaches and techniques that could be used in their own fields of expertise. We concentrated on three main subjects: – the geometrical description of Quantum Mechanics; – the Casimir effect and its mathematical implications; – the Quantum Zeno Effect and Open system dynamics. Each of these topics had a set of general lectures, aimed at presenting a global view on the subject, and other more technical seminars. We would like to thank all participants for their contribution to creating a wonderful scientific atmosphere during the Conference. We would especially like to thank the speakers and the authors of the papers contained in this volume, the members of the Scientific Committee for their guidance and support and, of course, the referees for their generous work. Special thanks are also due to the staff of the Centro de Ciencias de Benasque 'Pedro Pascual' who made this successful meeting possible. On behalf of the organising committee and the authors we would also like to acknowledge the partial support provided by the ESF-CASIMIR network ('New Trends and Applications of the Casimir Effect'), the QUITEMAD research Project (“Quantum technologies at Madrid”, Ref. Comunidad de Madrid P2009/ESP-1594), the MICINN Project (MTM2011-16027-E) and the Government from Arag´on (DGA) (DGA, Department of Industry and Innovation and the European Social Fund, DGA-Grant 24/1) who made the Conference and this Proceedings volume possible.
[en] Here, DarkSide (DS) at Gran Sasso underground laboratory is a direct Dark Matter search program based on Time Projection Chambers (TPC) with liquid Argon from underground sources. The DarkSide-50 (DS-50) TPC, with 150 kg of Argon is installed inside active neutron and muon detectors. DS-50 has been taking data since November 2013 with Atmospheric Argon (AAr) and since April 2015 with Underground Argon (UAr), depleted in radioactive "3"9Ar by a factor ~1400. The exposure of 1422 kg d of AAr has demonstrated that the operation of DS-50 for three years in a background free condition is a solid reality, thanks to the superb performance of the Pulse Shape Analysis. The first release of results from an exposure of 2616 kg d of UAr has shown no candidate Dark Matter events. We have set the best limit for Spin-Independent elastic nuclear scattering of WIMPs obtained by Argon-based detectors, corresponding to a cross-section of 2 10"–"4"4 cm"2 at a WIMP mass of 100 GeV. We present the detector design and performance, the results from the AAr run and the first results from the UAr run and we briefly introduce the future of the DarkSide program.
[en] The Bruno’s legacy of “neutrino oscillations” has been proved to exist. If we look back, early indications from experiments of the neutrino oscillations hypothesis, had arisen from two mysteries: 1) solar neutrino problem in late 1960’s (Homestake) 2) atmospheric neutrino anomaly in 1988 (Kamiokande).
[en] In Archaeometry, the collaboration among different specialists can be very useful to solve problems of authentication and to characterize the artworks. This cooperation is also recommended in radiocarbon dating. Before dating, for example, it is important to be aware of possible restorations undergone by the artworks and, in particular, which products have been used, since they may represent a source of contamination altering the obtained date. In fact, these products are generally organic compounds, thus representing an addition of exogenous carbon, which must be completely removed. In this paper, the case of the removal of synthetic resins will be discussed. The issue of contamination by synthetic resins will be presented using two case studies: the wooden frame of a Trittico by Ambrogio Lorenzetti and a painting on canvas of the first decades of the XX century.
[en] The intent of this issue of Il Nuovo Cimento Colloquia is to highlight the breadth and range of the research activities that have been presented at Nanoforum 2012 VIII edition held in Rome on September 24-26, 2012. The Nanoforum events are designed to offer a forum for the exchange of information on the latest progress in the exploiting field of nanotechnology. In addition to bringing together researchers involved in diverse R and D activities related to the 'nano' area, Nanoforum also endeavours to gather experts from industry. In doing so, Nanoforum provides a platform for researchers to discover new research opportunities, to identify the requirements for continued advancement in their field and to overcome the technological challenges related to nano materials production and applications. Emphasis is given to monitor progresses, to evaluate tendencies, to present innovative techniques and sophisticated strategies for materials growth and characterization at the nano scale. The papers published in this issue present an overview of some significant aspects of the nano technologies presented at Nanoforum 2012, covering current trends and developments in both basic and applied research. Topics range from the chemistry and physics of the synthesis/manufacturing processes, to characterization methodologies and to the engineering of nano materials for devices and bio-inspired applications. The editors are deeply grateful to all the authors for their inspiring contribution and precious collaboration.
[en] In this work the results of a dating study on bricks and mortars using both Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) are shown. The samples came from the outside walls of the Certosa di Pavia, located in northern Italy and independently dated (XVII-XVIII century). TL dating, applied to bricks using the fine grain technique, allowed to determine the time of manufacture of the bricks (XII century), that resulted therefore re-used. To circumvent this problem the application of two innovative dating techniques, OSL surface dating and mortar dating, was attempted. The first was applied to the light-shielded surfaces of bricks and allowed to successfully determine the edification of the wall (XVII century). Mortar dating gave instead severe age overestimation: the results obtained on coarse grain quartz with the SAR technique both on multi-grains aliquots and with single-grain analyses were highly dispersed indicating an incomplete bleaching of the quartz grains. The shine-down curves were in fact characterized by the absence of the so-called fast component, as confirmed by Linear Modulated OSL technique.