9 research outputs found

    Uncertainty Analysis in New Seismic Hazard Study of Spain Aimed at the Revision of the Spanish Building Code.

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    In this paper we present a global overview of the recent study carried out in Spain for the new hazard map, which final goal is the revision of the Building Code in our country (NCSE-02). The study was carried our for a working group joining experts from The Instituto Geografico Nacional (IGN) and the Technical University of Madrid (UPM) , being the different phases of the work supervised by an expert Committee integrated by national experts from public institutions involved in subject of seismic hazard. The PSHA method (Probabilistic Seismic Hazard Assessment) has been followed, quantifying the epistemic uncertainties through a logic tree and the aleatory ones linked to variability of parameters by means of probability density functions and Monte Carlo simulations. In a first phase, the inputs have been prepared, which essentially are: 1) a project catalogue update and homogenization at Mw 2) proposal of zoning models and source characterization 3) calibration of Ground Motion Prediction Equations (GMPE’s) with actual data and development of a local model with data collected in Spain for Mw < 5.5. In a second phase, a sensitivity analysis of the different input options on hazard results has been carried out in order to have criteria for defining the branches of the logic tree and their weights. Finally, the hazard estimation was done with the logic tree shown in figure 1, including nodes for quantifying uncertainties corresponding to: 1) method for estimation of hazard (zoning and zoneless); 2) zoning models, 3) GMPE combinations used and 4) regression method for estimation of source parameters. In addition, the aleatory uncertainties corresponding to the magnitude of the events, recurrence parameters and maximum magnitude for each zone have been also considered including probability density functions and Monte Carlo simulations The main conclusions of the study are presented here, together with the obtained results in terms of PGA and other spectral accelerations SA (T) for return periods of 475, 975 and 2475 years. The map of the coefficient of variation (COV) are also represented to give an idea of the zones where the dispersion among results are the highest and the zones where the results are robust

    Informe del sismo de Lorca del 11 de mayo de 2011

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    En la reciente historia sísmica de España, desde el terremoto de 1956 en Albolote (Granada) con once muertos y el de 1969 al SW del Cabo San Vicente con cuatro, el terremoto de Lorca de 11 de mayo de 2011 (magnitud 5.1) ha vuelto a ser especialmente importante por haber ocasionado nueve víctimas mortales. El movimiento sísmico, localizado muy próximo a la ciudad de Lorca, ha afectado directamente a más de 90.000 personas, que han sufrido sus consecuencias al registrarse con una intensidad de grado VII en la escala europea EMS, lo que ha motivado daños notables en las viviendas. El presente informe trata de reflejar las características del terremoto y de su serie de réplicas, recogiendo los trabajos que han desarrollado diferentes equipos de investigación, tanto previos al terremoto como posteriores. El estudio describe los aspectos científicos y técnicos de mayor interés, desde la historia sísmica de la zona hasta el comportamiento de las edificaciones de la ciudad de Lorca. Asimismo, se acompaña de un encuadre geológico de la zona y de las características de la falla de Alhama de Murcia, responsable de la ocurrencia del terremoto. Como consecuencia de los terremotos que hubo la misma zona en el año 2005, precedidos por un apreciable nivel de actividad sísmica en los años 1999 y 2002, la región de Murcia fue objeto del proyecto RISMUR, cofinanciado por el Instituto Geográfico Nacional y en el que participaron los redactores de este informe. Algunos de los aspectos de este proyecto, en concreto los relativos a la peligrosidad sísmica han sido incluidos, incidiendo en los resultados que se obtuvieron en la ciudad de Lorca. El informe va acompañado al final de una serie de conclusiones en relación con cada uno de los temas tratados, resaltando aquellos aspectos que se deberán tener en cuenta en futuros proyectos, a fin de mejorar por un lado el conocimiento de la sismicidad y peligrosidad sísmica y por otro para la adecuación de la normativa sismorresistente.Peer reviewe

    Microseismicity surveys of the fault-systems of S. E. Spain

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    Three microseismicity surveys were carried out in 1982, 1984 and 1985 in south-east Spain. The main survey was in 1984 with 24 seismic recording stations installed during 41 days. A total of 103 earthquakes were recorded with magnitudes between 0.5 and 3.9. Epicenters can be associated to faults in the area, which are shown to be seismically active. Larger activity is concentrated at the southern part of the area. Joint fault plane solutions show mecanism of fault with vertical motion of normal and reverse character.Part of this work has been supported by the DGICT, project PB-86-0431-C05 and the Comité Conjunto Hispano-Norteamericano para la cooperación cientifica y tecnologíca project CCA-8309/009.Peer reviewe

    Ciencia y persuasión social en la medicalización de la infancia en España, siglos XIX-XX Science and social persuasion in the medicalization of childhood in 19th- and 20th-century Spain

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    Este trabajo indaga la conversión en rutinaria de la visita del médico de niños en España. Estudia la sustitución de modelos de atención al embarazo, parto y crianza, tradicionalmente opacos para varones y objeto de cuidados mediante agentes populares, por otros accesibles a la medicina académica. A partir de la situación existente a nivel popular en el último tercio del siglo XIX, exploramos la repercusión de campañas de divulgación científica - entendidas como crítica sin cuartel a lo que se construyó como cultura popular - y la proliferación de dispositivos asistenciales gratuitos. La oferta de vigilancia sobre la alimentación de lactantes permitió familiarizar a las madres con la asistencia facultativa en la enfermedad, hasta que, en la segunda mitad del siglo XX, la Pediatría se centró preferentemente en las patologías y la Puericultura dejó de ser especialidad médica para convertirse en identidad profesional subalterna.<br>The article explores how childhood visits to doctors first became routine in Spain. The introduction of new models of prenatal care, childbirth, and childrearing required the extension of academic medicine into a terrain traditionally occupied by practitioners of popular medicine. Focusing on the status quo for most of the population in the final third of the nineteenth century, the study examines the repercussion of the era's scientific outreach campaigns (expressions of harsh criticism of what popular culture had constructed) and the spread of free health assistance. In particular, it highlights how attention to the nutritional needs of nursing mothers helped these women gain familiarity with the medical assistance available in the case of illness - so much so that by the second half of the twentieth century, the issues of health education and promotion had been relegated to a secondary plane within the medical profession

    HAWC and Fermi-LAT detection of extended emission from the unidentified source 2HWC J2006+341

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    The discovery of the TeV point source 2HWC J2006+341 was reported in the second HAWC gamma-ray catalog. We present a follow-up study of this source here. The TeV emission is best described by an extended source with a soft spectrum. At GeV energies, an extended source is significantly detected in Fermi-LAT data. The matching locations, sizes, and spectra suggest that both gamma-ray detections correspond to the same source. Different scenarios for the origin of the emission are considered and we rule out an association to the pulsar PSR J2004+3429 due to extreme energetics required, if located at a distance of 10.8 kpc.Universidad de Costa Rica/[112-B9-171]/UCR/Costa RicaUniversidad de Costa Rica/[112-B6-509]/UCR/Costa RicaUniversidad de Costa Rica/[829-B5-198]/UCR/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Físic

    The High-Altitude water cherenkov (HAWC) observatory in México: The primary detector

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    The High-Altitude Water Cherenkov (HAWC) observatory is a second-generation continuously operated, wide field-of-view, TeV gamma-ray observatory. The HAWC observatory and its analysis techniques build on experience of the Milagro experiment in using ground-based water Cherenkov detectors for gamma-ray astronomy. HAWC is located on the Sierra Negra volcano in México at an elevation of 4100 meters above sea level. The completed HAWC observatory principal detector (HAWC) consists of 300 closely spaced water Cherenkov detectors, each equipped with four photomultiplier tubes to provide timing and charge information to reconstruct the extensive air shower energy and arrival direction. The HAWC observatory has been optimized to observe transient and steady emission from sources of gamma rays within an energy range from several hundred GeV to several hundred TeV. However, most of the air showers detected are initiated by cosmic rays, allowing studies of cosmic rays also to be performed. This paper describes the characteristics of the HAWC main array and its hardware.UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Físic

    Combined dark matter searches towards dwarf spheroidal galaxies with Fermi-LAT, HAWC, H.E.S.S., MAGIC, and VERITAS

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    Cosmological and astrophysical observations suggest that 85\% of the total matter of the Universe is made of Dark Matter (DM). However, its nature remains one of the most challenging and fundamental open questions of particle physics. Assuming particle DM, this exotic form of matter cannot consist of Standard Model (SM) particles. Many models have been developed to attempt unraveling the nature of DM such as Weakly Interacting Massive Particles (WIMPs), the most favored particle candidates. WIMP annihilations and decay could produce SM particles which in turn hadronize and decay to give SM secondaries such as high energy γ\gamma rays. In the framework of indirect DM search, observations of promising targets are used to search for signatures of DM annihilation. Among these, the dwarf spheroidal galaxies (dSphs) are commonly favored owing to their expected high DM content and negligible astrophysical background. In this work, we present the very first combination of 20 dSph observations, performed by the Fermi-LAT, HAWC, H.E.S.S., MAGIC, and VERITAS collaborations in order to maximize the sensitivity of DM searches and improve the current results. We use a joint maximum likelihood approach combining each experiment's individual analysis to derive more constraining upper limits on the WIMP DM self-annihilation cross-section as a function of DM particle mass. We present new DM constraints over the widest mass range ever reported, extending from 5 GeV to 100 TeV thanks to the combination of these five different γ\gamma-ray instruments

    Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A

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