Looking for signatures of the Left-Right Twin Higgs model with the ATLAS detector at the LHC

The twin Higgs mechanism has recently been proposed to solve the little hierarchy problem. The phenomenology of this model is presented, and the possibility to observe some of the signatures predicted by this model using the ATLAS detector at the LHC is discussed

The ATLAS EventIndex: Full chain deployment and first operation

AbstractThe Event Index project consists in the development and deployment of a complete catalogue of events for experiments with large amounts of data, such as the ATLAS experiment at the LHC accelerator at CERN. Data to be stored in the EventIndex are produced by all production jobs that run at CERN or the GRID; for every permanent output file, a snippet of information, containing the file unique identifier and the relevant attributes for each event, is sent to the central catalogue. The estimated insertion rate during the LHC Run 2 is about 80 Hz of file records containing ∼15 kHz of event records. This contribution describes the system design, the initial performance tests of the full data collection and cataloguing chain, and the project evolution towards the full deployment and operation by the end of 2014

Spanish ATLAS tier-2: Facing up to LHC Run 2

The goal of this work is to describe the way of addressing the main challenges of Run 2 by the Spanish ATLAS Tier-2. The considerable increase of energy and luminosity for the upcoming Run 2 with respect to Run 1 has led to a revision of the ATLAS computing model as well as some of the main ATLAS computing tools. In this paper, the adaptation to these changes will be described. The Spanish ATLAS Tier-2 is a R&D project which consists of a distributed infrastructure composed of three sites and its members are involved in ATLAS computing progress, namely the work in different tasks and the development of new tools (e.g. Event Index)This work has been supported by MINECO, Spain (Proj. Ref. FPA2010-21919-C03-01,02,03 & FPA2013-47424-C3,01,02,03), which include FEDER funds from the European Unio

Estudio de inmunogenicidad para dos vacunas recombinantes contra hepatitis B

This study compares the immunogenicity (seroconversion, seroprotection and hiperesponse) produced by two hepatitis B recombinant vaccines (Engerix- B Belge and Cuban). For this purpose two sketches were used (012 and 016 months). The anti-HBs quantification was performed by using Abbott and Organon methods in order to compare its results. In the study 257 volunteers were distributed in four groups to the hapazard (two vaccines and two sketches). Results: the Abbott and Organon methods did not show any statistically significant difference. The Cuban vaccine shows greater immunogenous response for two doses and 012 sketch. There are no differences between sketch 012 and 016 with the Cuban vaccine. The scheme 016 did not show statistically significant difference for the Engerix-B Belge vaccine. The last mentioned vaccine showed to be better with the 016 scheme.Este estudio compara la inmunogenicidad (seroconversión, seroprotección e Hiperrespuesta), producida por dos vacunas recombinantes contra la hepatitis B (Engerix-B de Bélgica y Cubana), en dos esquemas (012 y 016 meses), empleando los métodos de cuantificación para Anti-HBsAg (Abbott y Organón), los cuales fueron también comparados. En el estudio participaron 257 voluntarios,  divididos al azar en 4 grupos (dos vacunas, dos esquemas). Resultados: los dos métodos de Abbon y Organon, no presentan diferencias estadísticas significativas. La vacuna cubana muestra una mayor respuesta inmunogénica para dos dosis de vacuna y para el esquema 012. No hay diferencia entre los esquemas 012 y 016 y en el esquema 016 no se ven diferencias estadísticamente significativas con la vacuna Engerix-B. En esta Última el esquema 016 muestra mejores resultados que el 012

Revista de Vertebrados de la Estación Biológica de Doñana

La reproducción de Hyla meridionalis en el suroeste de EspañaAlimentación y relaciones tróficas entre larvas de Triturus marmoratus, T. alpestris y T. helveticus (Amphibia: CaudataOrganization of behaviour in isolated lizards (Gallotia galloti galloti) as revealed by multivariate analyseComposición y estructura de las comunidades de aves a lo largo de un gradiente altitudinal en tres medios arbustivos del macizo de Ayllón(Sistema Central)La comunidad de aves de un acebuchar del sur de España durante el periodo invernal y de cria.Alimentación del buho chico (Asio otus) en la isla de Tenerife y análisis comparativo con la dieta de Tyto albaAlimentación del zorzal charlo (Turdus viscivoros) en la sierra de Cazorla, SE de España.La migración en España del verderón común (Carduelis chloris, L.) según los resultados de anillamientoIdentificación de los principales quirópteros ibéricos a partir de sus dientes aislados. Valor sistemático de los caracteres morfológicos y métricos dentariosRitmo de actividad en Gazella dorcasSobre la sistemática y biología de Eliomys quercinus en la Cordillera Cantábrica.Primeras citas de Barbus microcephalus Almaça, 1967 (Ostariophysi: Cyprinidae) en EspañaSobre la presencia de Lampetra planeri BLOCH, 1784 en España.Sobre el status taxonómico del género Valencia Myers, 1928 en el suroeste de IberiaNuevas localidades de Chondrostroma polypis Steindachner, 1865 (Ostariophysi, Cyprinidae) en España.Sobre la distribución Gobio gobio (L., 1758)(OSTAOPHYSI, CIPRINIDAE) en EspañaNotas sobre la alimentación de larvas de anfibios: 2. Salamandra salamandra de CazorlaNuevos datos sobre la permanencia de caracteres larvarios en individuos adultos de una población de tritón pirenaico (Euproctus asper) en el valle de AránLa variación del diseño natural como método de reconocimiento individual en Triturus boscaiPresencia de Triturus boscai en la provincia de Córdoba.Datos sobre la alimentación de Athene cunicularia en la Reserva de fauna altoandina de Ulla-Ulla, Bolivia.Falco peregrinus cassini en BoliviaAlgunos datos sobre quirópteros de Galicia.Notas sobre la alimentación de la nutria (Lutra lutra) en el embalse de Matavacas, HuelvaPeer reviewe

Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

Measurement of the production of a W boson in association with a charm quark in pp collisions at √s = 7 TeV with the ATLAS detector

The production of a W boson in association with a single charm quark is studied using 4.6 fb−1 of pp collision data at s√ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26−0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ(W + +c¯¯)/σ(W − + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s−s¯¯¯ quark asymmetry

Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at s√=8 TeV with ATLAS

Measurements of fiducial and differential cross sections are presented for Higgs boson production in proton-proton collisions at a centre-of-mass energy of s√=8 TeV. The analysis is performed in the H → γγ decay channel using 20.3 fb−1 of data recorded by the ATLAS experiment at the CERN Large Hadron Collider. The signal is extracted using a fit to the diphoton invariant mass spectrum assuming that the width of the resonance is much smaller than the experimental resolution. The signal yields are corrected for the effects of detector inefficiency and resolution. The pp → H → γγ fiducial cross section is measured to be 43.2 ±9.4(stat.) − 2.9 + 3.2 (syst.) ±1.2(lumi)fb for a Higgs boson of mass 125.4GeV decaying to two isolated photons that have transverse momentum greater than 35% and 25% of the diphoton invariant mass and each with absolute pseudorapidity less than 2.37. Four additional fiducial cross sections and two cross-section limits are presented in phase space regions that test the theoretical modelling of different Higgs boson production mechanisms, or are sensitive to physics beyond the Standard Model. Differential cross sections are also presented, as a function of variables related to the diphoton kinematics and the jet activity produced in the Higgs boson events. The observed spectra are statistically limited but broadly in line with the theoretical expectations