1000 resultados para VISTA VARIABLES


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We describe the public ESO near-IR variability survey (VVV) scanning the Milky Way bulge and an adjacent section of the mid-plane where star formation activity is high. The survey will take 1929 h of observations with the 4-m VISTA telescope during 5 years (2010-2014), covering similar to 10(9) point sources across an area of 520 deg(2), including 33 known globular clusters and similar to 350 open clusters. The final product will be a deep near-IR atlas in five passbands (0.9-2.5 mu m) and a catalogue of more than 106 variable point sources. Unlike single-epoch surveys that, in most cases, only produce 2-D maps, the VVV variable star survey will enable the construction of a 3-D map of the surveyed region using well-understood distance indicators such as RR Lyrae stars, and Cepheids. It will yield important information on the ages of the populations. The observations will be combined with data from MACHO, OGLE, EROS, VST, Spitzer, HST, Chandra, INTEGRAL, WISE, Fermi LAT, XMM-Newton, GAIA and ALMA for a complete understanding of the variable sources in the inner Milky Way. This public survey will provide data available to the whole community and therefore will enable further studies of the history of the Milky Way, its globular cluster evolution, and the population census of the Galactic Bulge and center, as well as the investigations of the star forming regions in the disk. The combined variable star catalogues will have important implications for theoretical investigations of pulsation properties of stars. (C) 2009 Elsevier B.V. All rights reserved.

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Context. The ESO public survey VISTA variables in the Via Lactea (VVV) started in 2010. VVV targets 562 sq. deg in the Galactic bulge and an adjacent plane region and is expected to run for about five years. Aims. We describe the progress of the survey observations in the first observing season, the observing strategy, and quality of the data obtained. Methods. The observations are carried out on the 4-m VISTA telescope in the ZYJHK(s) filters. In addition to the multi-band imaging the variability monitoring campaign in the K-s filter has started. Data reduction is carried out using the pipeline at the Cambridge Astronomical Survey Unit. The photometric and astrometric calibration is performed via the numerous 2MASS sources observed in each pointing. Results. The first data release contains the aperture photometry and astrometric catalogues for 348 individual pointings in the ZYJHK(s) filters taken in the 2010 observing season. The typical image quality is similar to 0 ''.9-1 ''.0. The stringent photometric and image quality requirements of the survey are satisfied in 100% of the JHK(s) images in the disk area and 90% of the JHK(s) images in the bulge area. The completeness in the Z and Y images is 84% in the disk, and 40% in the bulge. The first season catalogues contain 1.28 x 10(8) stellar sources in the bulge and 1.68 x 10(8) in the disk area detected in at least one of the photometric bands. The combined, multi-band catalogues contain more than 1.63 x 10(8) stellar sources. About 10% of these are double detections because of overlapping adjacent pointings. These overlapping multiple detections are used to characterise the quality of the data. The images in the JHK(s) bands extend typically similar to 4 mag deeper than 2MASS. The magnitude limit and photometric quality depend strongly on crowding in the inner Galactic regions. The astrometry for K-s = 15-18 mag has rms similar to 35-175 mas. Conclusions. The VVV Survey data products offer a unique dataset to map the stellar populations in the Galactic bulge and the adjacent plane and provide an exciting new tool for the study of the structure, content, and star-formation history of our Galaxy, as well as for investigations of the newly discovered star clusters, star-forming regions in the disk, high proper motion stars, asteroids, planetary nebulae, and other interesting objects.

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Context. It is not known how many globular clusters may remain undetected towards the Galactic bulge. Aims. One of the aims of the VISTA Variables in the Via Lactea (VVV) Survey is to accurately measure the physical parameters of the known globular clusters in the inner regions of the Milky Way and search for new ones, hidden in regions of large extinction. Methods. From deep near-infrared images, we derive deep JHK(S)-band photometry of a region surrounding the known globular cluster UKS 1 and reveal a new low-mass globular cluster candidate that we name VVV CL001. Results. We use the horizontal-branch red clump to measure E(B-V) similar to 2.2 mag, (m - M)(0) = 16.01 mag, and D = 15.9 kpc for the globular cluster UKS 1. On the basis of near-infrared colour-magnitude diagrams, we also find that VVV CL001 has E(B-V) similar to 2.0, and that it is at least as metal-poor as UKS 1, although its distance remains uncertain. Conclusions. Our finding confirms the previous projection that the central region of the Milky Way harbours more globular clusters. VVV CL001 and UKS 1 are good candidates for a physical cluster binary, but follow-up observations are needed to decide if they are located at the same distance and have similar radial velocities.

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Context. VISTA Variables in the Via Lactea (VVV) is one of the six ESO Public Surveys operating on the new 4-m Visible and Infrared Survey Telescope for Astronomy (VISTA). VVV is scanning the Milky Way bulge and an adjacent section of the disk, where star formation activity is high. One of the principal goals of the VVV Survey is to find new star clusters of different ages. Aims. In order to trace the early epochs of star cluster formation we concentrated our search in the directions to those of known star formation regions, masers, radio, and infrared sources. Methods. The disk area covered by VVV was visually inspected using the pipeline processed and calibrated K(S)-band tile images for stellar over-densities. Subsequently, we examined the composite JHK(S) and ZJK(S) color images of each candidate. PSF photometry of 15 x 15 arcmin fields centered on the candidates was then performed on the Cambridge Astronomy Survey Unit reduced images. After statistical field-star decontamination, color-magnitude and color-color diagrams were constructed and analyzed. Results. We report the discovery of 96 new infrared open clusters and stellar groups. Most of the new cluster candidates are faint and compact (with small angular sizes), highly reddened, and younger than 5 Myr. For relatively well populated cluster candidates we derived their fundamental parameters such as reddening, distance, and age by fitting the solar-metallicity Padova isochrones to the color-magnitude diagrams.

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VISTA Variables in the Via Lactea (VVV) is an ESO variability survey that is performing observations in near-infrared bands (ZY JHK(s)) toward the Galactic bulge and part of the disk with the completeness limits at least 3 mag deeper than Two Micron All Sky Survey. In the present work, we searched in the VVV survey data for background galaxies near the Galactic plane using ZY JHK(s) photometry that covers 1.636 deg(2). We identified 204 new galaxy candidates by analyzing colors, sizes, and visual inspection of multi-band (ZY JHK(s)) images. The galaxy candidate colors were also compared with the predicted ones by star count models considering a more realistic extinction model at the same completeness limits observed by VVV. A comparison of the galaxy candidates with the expected one by Millennium simulations is also presented. Our results increase the number density of known galaxies behind the Milky Way by more than one order of magnitude. A catalog with galaxy properties including ellipticity, Petrosian radii, and ZY JHK(s) magnitudes is provided, as well as comparisons of the results with other surveys of galaxies toward the Galactic plane.

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Context. The Milky Way (MW) bulge is a fundamental Galactic component for understanding the formation and evolution of galaxies, in particular our own. The ESO Public Survey VISTA Variables in the Via Lactea is a deep near-IR survey mapping the Galactic bulge and southern plane. Particularly for the bulge area, VVV is covering similar to 315 deg(2). Data taken during 2010 and 2011 covered the entire bulge area in the JHKs bands. Aims. We used VVV data for the whole bulge area as a single and homogeneous data set to build for the first time a single colour-magnitude diagram (CMD) for the entire Galactic bulge. Methods. Photometric data in the JHK(s) bands were combined to produce a single and huge data set containing 173 150 467 sources in the three bands, for the similar to 315 deg(2) covered by VVV in the bulge. Selecting only the data points flagged as stellar, the total number of sources is 84 095 284. Results. We built the largest colour-magnitude diagrams published up to date, containing 173.1+ million sources for all data points, and more than 84.0 million sources accounting for the stellar sources only. The CMD has a complex shape, mostly owing to the complexity of the stellar population and the effects of extinction and reddening towards the Galactic centre. The red clump (RC) giants are seen double in magnitude at b similar to -8 degrees-10 degrees, while in the inner part (b similar to -3 degrees) they appear to be spreading in colour, or even splitting into a secondary peak. Stellar population models show the predominance of main-sequence and giant stars. The analysis of the outermost bulge area reveals a well-defined sequence of late K and M dwarfs, seen at (J - K-s) similar to 0.7-0.9 mag and K-s greater than or similar to 14 mag. Conclusions. The interpretation of the CMD yields important information about the MW bulge, showing the fingerprint of its structure and content. We report a well-defined red dwarf sequence in the outermost bulge, which is important for the planetary transit searches of VVV. The double RC in magnitude seen in the outer bulge is the signature of the X-shaped MW bulge, while the spreading of the RC in colour, and even its splitting into a secondary peak, are caused by reddening effects. The region around the Galactic centre is harder to interpret because it is strongly affected by reddening and extinction.

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Context. VISTA Variables in the Vía Láctea (VVV) is one of six ESO Public Surveys using the 4 meter Visible and Infrared Survey Telescope for Astronomy (VISTA). The VVV survey covers the Milky Way bulge and an adjacent section of the disk, and one of the principal objectives is to search for new star clusters within previously unreachable obscured parts of the Galaxy. Aims. The primary motivation behind this work is to discover and analyze obscured star clusters in the direction of the inner Galactic disk and bulge. Methods. Regions of the inner disk and bulge covered by the VVV survey were visually inspected using composite JHKS color images to select new cluster candidates on the basis of apparent overdensities. DR1, DR2, CASU, and point spread function photometry of 10 × 10 arcmin fields centered on each candidate cluster were used to construct color–magnitude and color–color diagrams. Follow-up spectroscopy of the brightest members of several cluster candidates was obtained in order to clarify their nature. Results. We report the discovery of 58 new infrared cluster candidates. Fundamental parameters such as age, distance, and metallicity were determined for 20 of the most populous clusters.

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I.-Desvelar cómo vive la mujer su desarrollo profesional, laboral y personal, su dedicación a éstas tareas, y cómo se la puede apoyar convenientemente en su desarrollo, a partir de las pertinentes y convenientes actuaciones en Formación del Profesorado.II.-Analizar las variables que conviene considerar a la hora de plantearse la Formación, tanto Inicial como Continuada, de las Maestras de Educación Infantil. Muestra representativa de 286 docentes de Educación Infantil, de una población total de 755 en toda la geografía Navarra: urbana y rural. Una vez clarificado el tema de análisis a nivel teórico, se procede a elaborar un cuestionario que se pasa a la muestra.Cada cuestionario va acompañado de una entrevista personal clarificadora en relación a los contenidos del cuestionario y a las diferentes percepciones sobre el tema. El cuestionario consta de 154 ítems, y al igual que la entrevista, pretende conseguir información acerca de problemas de salud físico-psíquicos, de desarrollo personal, social y profesional. I.-Constituyen un colectivo poco dinámico ( la edad tardía de jubilación, está prácticamente cerrada la oferta de empleo público.. ). II.-Profesionales con sobrecarga de trabajo ( falta de tiempo para la realización de tareas profesionales y domésticas ). III.-Tienen sentimientos de satisfacción por las prestaciones que tienen por su trabajo ( sueldo fijo, no tener riesgo de despido, largas vacaciones, acceso fácil a créditos bancarios.. ). IV.-En cuanto a la Formación Inicial, la mayoría de las maestras en activo se han formado siguiendo planes de estudio anteriores a 1990. Este aspecto es importante a la hora de diseñar los planes de Formación Permanente. V.-Es alta la participación de las maestras de Educación Infantil en actividades de Formación Permanente planificadas por la Administración Educativa. VI.-A la hora de formar los equipos docentes, se evidencia la no existencia de colaboración entre los profesionales. No se ha vencido todavía el aislamiento profesional. VII.-Las variables a tener en cuenta para dar salida positiva a estas cuestiones son: las profesionales (mujeres), el contexto, la evolución del conocimiento, estrategias de enseñanza, cultura de colaboración, el proceso de cambio y el valor moral de la educación.

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Forest fires are a serious threat to humans and nature from an ecological, social and economic point of view. Predicting their behaviour by simulation still delivers unreliable results and remains a challenging task. Latest approaches try to calibrate input variables, often tainted with imprecision, using optimisation techniques like Genetic Algorithms. To converge faster towards fitter solutions, the GA is guided with knowledge obtained from historical or synthetical fires. We developed a robust and efficient knowledge storage and retrieval method. Nearest neighbour search is applied to find the fire configuration from knowledge base most similar to the current configuration. Therefore, a distance measure was elaborated and implemented in several ways. Experiments show the performance of the different implementations regarding occupied storage and retrieval time with overly satisfactory results.

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Objective: To identify and prioritize improvement opportunities, according to the European Foundation for Quality Management model (EFQM) model, of the methadone dispensing service in Andalusian Primary Health Care, from the point of view of professionals. Method: Delphi consensus method, implemented from September 2007 to March 2008 by means of three rounds of interviews with questionnaires administered by electronic mail to 39 professionals. The Panel of experts was made up of Dispensers and Prescribers of methadone as well as Coordinators of welfare services from the Methadone Treatment Program (MTP). Selection criteria were: Being in active employment with a minimum of 3 years experience. Sample diversification variables: Professional role, geographical environment and type of habitat. Recruitment: By means of key professional bodies from different institutions. Results: 48 improvement opportunities were identified. Thirteen of these obtained a high level of agreement in the final round. According to the EFQM model, the dimensions that obtained the most consensus in relation to improving the care service were: Leadership, Alliances and Resources. The dimension that caused the greatest disagreement was Processes. Conclusions: In spite of its having been implemented since 1997 in Andalusian Primary Health Care, the methadone dispensing service is at an implementation phase, rather than what could be classed as a fully deployed stage

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Demostrar cómo influyen en el rendimiento académico del niño los factores personales y familiares, como la atención, historia del niño y el clima educativo familiar en el que vive. Alumnos de cuarto curso de EGB, de dos colegios privados de Granada. Aplicación de tests y pruebas, atendiendo a distintas variables, como la variable fisiológica, variable atención y variable clima familiar. Variable fisiológica: cuestionario anamnésico, fichas psicomédicas existentes en los colegios, la tabla y el peso, la vista y el oído. Variable atención: prueba de punteado de M. Stambak, prueba de frenado voluntario de A. Rey, prueba de punteo de R. Perron, tachado de signos de R. Zazzo. Clima familiar: cuestionario y entrevistas a las madres. Análisis estadísticos y gráficos. Variable fisiológica: el rendimiento es influenciado por los factores fisiológicos y de desarrollo; no se haya diferencia significativa en el apartado: actitud ante el embarazo y circunstancias perinatales; el apartado sueño, diferencia significativamente tanto a los alumnos adelantados como a los retrasados, en cuanto a la duración del mismo. Variabe atención: el grupo de alumnos adelantados, ejecuta siempre mejor la tarea propuesta; respecto a la precisión o al número de errores cometidos en la prueba de punteados, los dos grupos se comportan de forma semejante. Variable clima familiar: existe un mayor acuerdo entre los padres y madres del grupo de alumnos adelantados que en los padres del grupo aparejado; los padres de alumnos adelantados poseen un trato mas constante, que les hace manifestarse de modo más estable; respecto a los niveles de autoridad de los padres, discrimina significativamente a ambos grupos la rigidez a la hora de practicarla. Como conclusión general, de las tres variables, se puede afirmar que la hipótesis en que fue formulada: los factores fisiológicos, especialmente las afecciones de carácter crónico, la atención y el clima familiar son determinantes del rendimiento escolar.

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Se pretende lograr tres objetivos: 1. Identificar la figura del nieto favorito; 2. Conocer la relación existente entre las características de la figura del nieto favorito, la participación del abuelo en actividades con su nieto y la imagen que los abuelos tienen de la relación con las características del abuelo; y 3. Estudiar la relación existente entre las actividades conjuntas entre el nieto y el abuelo, y la imagen que los abuelos tienen de la relación con las características del nieto favorito. 603 abuelos y abuelas de Burgos capital y provincia, distribuidos en cuatro grupos atendiendo a la edad: menor de 65, entre 65 y 74, entre 75 y 84 y mayor de 84. Para comprender la relación entre abuelos y nietos y determinar qué variables la condicionan se han planteado cuatro objetivos: El primero es el análisis descriptivo de las características sociodemográficas de los abuelos; el segundo, el análisis de las características del nieto favorito, actividades conjuntas e imagen de la relación; el tercero, el análisis de la figura del nieto favorito, actividades conjuntas e imagen de la relación de acuerdo a las características sociodemográficas del abuelo; y el cuarto, el análisis de las actividades que realiza el abuelo con nieto y su imagen de la relación según las características del nieto favorito. El instrumento utilizado es el cuestionario de Rico et al. (2001). El estudio de los datos encontrados se realizó a través del paquete estadístico SPSS 11.5. Con respecto a los análisis para establecer relaciones significativas se ha usado la prueba del Chi-cuadrado y para las pruebas no paramétricas se han usado tablas de contingencia. Los resultados indican que el nieto favorito de los abuelos o con el que mayor frecuencia de contacto tienen, es varón, perteneciente a la línea materna, tiene menos de 10 años, y es primogénito entre los nietos. Las actividades que con mayor periodicidad realiza el abuelo con el nieto son, por este orden: cuidarle, explicarle cosas, jugar, hablar por teléfono, contar cuentos e historias, ver la televisión, ir de paseo y acompañarle al colegio. Las funciones que en mayor medida realiza el abuelo con el nieto son: la de consentidor, la de amor incondicional, y transmisor de conocimientos y valores. Las variables del abuelo que mayor relación tienen con las características sociodemográficas del nieto con las actividades conjuntas son: la edad, el tiempo que lleva siendo abuelo y el número de nietos, y con las imágenes de la relación el sexo. Las variables del nieto que se relacionan, en mayor medida, con las actividades conjuntas son: el lugar de residencia, la frecuencia de contacto y la convivencia con algún abuelo; y las características del nieto que más inciden en la imagen que tienen los abuelos de la relación son: la edad del nieto, los estudios que realiza, el número de hermanos del nieto y la existencia de discapacidad. Con esta investigación se abren futuras líneas de trabajo, siendo los próximos pasos: 1.Analizar la relación abuelo-nieto desde la perspectiva de nietos de diferentes edades; 2. Analizar esa relación con parejas de abuelos y nietos para contrastar la información; y 3. Analizarla desde una perspectiva intercultural para lo que se cuenta con muestras de Guatemala y El Salvador.

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Resumen tomado de la revista. La publicación recoge resumen en Inglés

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Resumen tomado de la publicación. Resumen en inglés

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Elaborar y evaluar una escala para medir la conciencia lectora de los alumnos de once y doce años. Alumnos de primero de ESO en cinco colegios de la Comunidad de Madrid. Se parte del análisis de las teorías y metodologías vigentes en el campo de la metacomprensión lectora para construir un instrumento que mide los procesos y variables metacognitivos implicados en la actividad de la lectura. Su nombre es ESCOLA (Escala de Conciencia Lectora) y se evalúa su utilidad a partir de la respuesta de los sujetos a los que se aplica. Además, se incluye una versión reducida de ESCOLA llamada Módulo D-35, que es una escala de respuesta dicotómica que facilita la detección de sujetos con baja conciencia lectora. Se utilizan las escalas ESCOLA, Módulo D-35 y Likert como instrumentos de medición. La investigación es de carácter experimental. La aplicación de ESCOLA permite descubrir el grado de conciencia lectora de los estudiantes y en qué medida son capaces de planificar, supervisar y evaluar la actividad de la lectura. Esta investigación aporta un material útil para determinar si el alumno es o no un lector estratégico desde el punto de vista de la metacognición. Además, el conocimiento de las habilidades de los alumnos en materia de lectura permite prever su grado de adquisición de conocimientos en clase ya que la mayor parte del aprendizaje se realiza a través de la lectura de textos.