111 research outputs found

    Ordered and Oriented Supramolecular n/p-Heterojunction Surface Architectures: Completion of the Primary Color Collection

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    In this study, we describe synthesis, characterization, and zipper assembly of yellow p-oligophenyl naphthalenediimide (POP-NDI) donor−acceptor hybrids. Moreover, we disclose, for the first time, results from the functional comparison of zipper and layer-by-layer (LBL) assembly as well as quartz crystal microbalance (QCM), atomic force microscopy (AFM), and molecular modeling data on zipper assembly. Compared to the previously reported blue and red NDIs, yellow NDIs are more π-acidic, easier to reduce, and harder to oxidize. The optoelectronic matching achieved in yellow POP-NDIs is reflected in quantitative and long-lived photoinduced charge separation, comparable to their red and much better than their blue counterparts. The direct comparison of zipper and LBL assemblies reveals that yellow zippers generate more photocurrent than blue zippers as well as LBL photosystems. Continuing linear growth found in QCM measurements demonstrates that photocurrent saturation at the critical assembly thickness occurs because more charges start to recombine before reaching the electrodes and not because of discontinued assembly. The found characteristics, such as significant critical thickness, strong photocurrents, large fill factors, and, according to AFM images, smooth surfaces, are important for optoelectronic performance and support the existence of highly ordered architectures

    Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

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    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

    Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

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    We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

    Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

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    Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson

    Standalone vertex finding in the ATLAS muon spectrometer

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    A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

    Measurement of the top quark pair cross section with ATLAS in pp collisions at √s=7 TeV using final states with an electron or a muon and a hadronically decaying τ lepton

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    A measurement of the cross section of top quark pair production in proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 7 TeV is reported. The data sample used corresponds to an integrated luminosity of 2.05 fb -1. Events with an isolated electron or muon and a τ lepton decaying hadronically are used. In addition, a large missing transverse momentum and two or more energetic jets are required. At least one of the jets must be identified as originating from a b quark. The measured cross section, σtt-=186±13(stat.)±20(syst.)±7(lumi.) pb, is in good agreement with the Standard Model prediction

    Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb−1 of √s=7 TeV proton-proton collisions

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    Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb−1 of pp collision data at s√=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV

    Reseñas de libros

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    Carrasca Hortal, José y Millán Gómez, Antonio. La Estructura Gótica Catalana. Sobre los conceptos de media y espacio. El problema de la forma en la cubierta (Por Antonio Millán) pp. 4.-- Verd Herrero, Antonio. Dibujo del natural. Manual de texto docente universitario (Por Antonio Verd) pp.5-6.-- Caninva, Luigi. L'Architettura romana (Por Carlos de San Antonio Gómez) pp.6-7.-- Villalobos Alonso, Daniel. La mirada de Fisac (Por Alberto Grijalba Bengoetxea)pp.8.-- Jiménez Martín, Alfonso et al. La catedral gótica de Sevilla. Fundación y fábrica de la obra nueva (Por Enrique Rabasa Díaz) pp.8-9.-- García-Gutiérrez Mosteiro, Javier. Narciso Pascual y Colomer (1808-1870). Arquitecto del Madrid isabelino (Por Enrique Rabasa Díaz) pp.9-10.-- Valladolid. Bellido Blanco, Santiago. Cuaderno de apuntes (Por Fernando Lmares García) pp.10-11.-- Lopez-Peláez, José Manuel. Maestros cercanos de un arquitecto (Por Javier García-Gutiérrez Masteiro) pp.12.-- Garcia Bueno, Antonio. Dibujando la Alhambra (Por Joaquín Casado de Amezúa Vázquez) pp.13-14.-- Chías Navarro, Pilar y Abad Balboa, Tomás. Eduardo Torroja. Obras y proyectos (Por Jorge Llopis Verdú) pp.14-15.-- Gómez i Serrano, Josep y Font, Juan. La forma de la Villa de Madrid. Soporte gráfico para la información histórica de la ciudad (Por Jorge Llopis Verdú) pp.15-16.-- Nagore, Fernando. Geometría métrica y descriptiva para arquitectos (Por José Antonio Ruiz de le Rosa) pp.16-17.-- Rabasa Diaz, Enrique y el Centro de los Oficios de LeónGuía práctica de la estereotomía de la piedra (Por José CalvoLópez) pp.18-19.-- Hernández Iviartinez, Ascensión. La clonación arquitectónica (Por José Joaquín Parra 8añón) pp.20-21.-- Gentil Baldrich, José María y Yanguas Álvarez de Toledo, Ana. Fernando Barquín y Barón Joaquín Barquín y Barón Imágenes de su archivo en los fondos FIDAS (Por José Manuel Pala) pp.21-22.-- Escoda Pastor, Carmen. El magnetismo del lugar en la arquitectura pp.23.-- Herrero Vázquez, Eduardo Alejandro. Compases de mano, compases de ojo: la Geometrización de la Realidad según Laussedat (POr Adrien Javary) pp.24-25.-- Castaño Perea, Enrique. Arquitectura y música: Policoralidad en la Capilla Real del Alcázar de Madrid pp.25-26.-- Piquer Cases, Juan Carlos. Los modelos digitales en la arquitectura, desarrollo del proyecto e investigación patrimonial. Palacio Real de Valencia (1239-1810): análisis y reconstrucción virtual sobre la planta de Vicente Gascó de 1761 (Por Juan Carlos Piquer Cases) pp.26-28.-- Pérez Naya, Antonia. Arquitectura del silencio y la memoria. Análisis de los cementerios de la Costa da Morte gallega (Por JAfT) pp. 28-29.-- Falcón Meraz, José Manuel. La expresión de una línea museística singular (Por Juan Puebla) pp.29-30.-- 11Seminario Internacional "Color en el Diseño y la Arquitectura" pp.32.-- Taller de Pintura con Antonio López E.T.S. de Pamplona, septiembre de 2006 y 2007 (Por Inmacu/ada .liméne: Cabal/ero) pp.32-35.-- Arquitectura y autopsia: análisis gráficos de algunos restos de la inexistente Universidad laboral de Sevilla (Por José Joaquín Parra Bañón) pp.36-37Milán Gómez, A.; Verd Herrero, A.; De San Antonio Gomez, JC.; Grijalba Bengoetxea, A.; Rabasa Díaz, E.; Linares García, F.; García-Gutiérrez Mosteiro, J.... (2008). Reseñas de libros. EGA Expresión Gráfica Arquitectónica. 13(13):4-37. https://doi.org/10.4995/ega.2008.10266OJS437131

    Search for anomalous production of prompt like-sign muon pairs and constraints on physics beyond the standard model with the ATLAS detector

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    Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMAn inclusive search for anomalous production of two prompt, isolated muons with the same electric charge is presented. The search is performed in a data sample corresponding to 1.6 fb-1 of integrated luminosity collected in 2011 at √s = 7 TeV with the ATLAS detector at the LHC. Muon pairs are selected by requiring two isolated muons of the same electric charge with pT > 20 GeV and |η| < 2.5. Minimal requirements are placed on the rest of the event activity. The distribution of the invariant mass of the muon pair m(μμ) is found to agree well with the background expectation. Upper limits on the cross section for anomalous production of two muons with the same electric charge are placed as a function of m(μμ) within a fiducial region defined by the event selection. The fiducial cross-section limit constrains the like-sign top-quark pair-production cross section to be below 3.7 pb at 95% confidence level. The data are also analyzed to search for a narrow like-sign dimuon resonance as predicted for e.g. doubly charged Higgs bosons (H±±). Assuming pair production of H±± bosons and a branching ratio to muons of 100% (33%), this analysis excludes masses below 355 (244) GeV and 251 (209) GeV for H±± bosons coupling to left-handed and right-handed fermions, respectivelyWe acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF, DNSRC and Lundbeck Foundation, Denmark; ARTEMIS, European Union; IN2P3-CNRS, CEA-DSM/IRFU, France; GNAS, Georgia; BMBF, DFG, HGF, MPG and AvH Foundation, Germany; GSRT, Greece; ISF, MINERVA, GIF, DIP and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; RCN, Norway; MNiSW, Poland; GRICES and FCT, Portugal; MERYS (MECTS), Romania; MES of Russia and ROSATOM, Russian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and MVZT, Slovenia; DST/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF and Cantons of Bern and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the Royal Society and Leverhulme Trust, United Kingdom; DOE and NSF, United States of America. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular, from CERN and the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFNCNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL (USA) and in the Tier-2 facilities worldwid
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