Photometric study of the double cluster h and chi Persei

We present uvbybeta CCD photometry of the central region of the double cluster h and chi Persei. We identify 350 stars, of which 214 were not included in Oosterhof catalogue. Our magnitude limit V=16.5 allows us to reach early F spectral type and obtain very accurate fits to the ZAMS. We derive reddening values of E(b-y)=0.44+-0.02 for h Persei and E(b-y)=0.39+-0.05 for chi Persei. From the ZAMS fitting, we derive distance moduli V0-Mv=11.66+-0.20 and V0-Mv=11.56+-0.20 for h and chi Persei respectively. These values are perfectly compatible with both clusters being placed at the same distance and having identical reddenings. The shift in the main-sequence turnoff and isochrone fitting, however, show that there is a significant age difference between both clusters, with the bulk of stars in h Persei being older than chi Persei. There is, however, a significant population of stars in h Persei which are younger than chi Persei. All this argues for at least three different epochs of star formation, corresponding approximately to log t=7.0, 7.15 and 7.3.Comment: 47 pages, 15 figures and 29 tables. Uses aa.cls. Accepted for publication in the Astronomy and Astrophysic

The open cluster Pismis 11 and the very luminous blue supergiant HD 80077

(Abridged) The very luminous blue supergiant HD 80077 has been claimed to be a member of the young open cluster Pismis 11, and hence a hypergiant. We obtained UBVRI photometry of the cluster field and low-resolution spectroscopy of a number of putative members. We derive spectral types from the spectra and determine that the reddening in this direction is standard. We then carry out a careful photometric analysis that allows us to determine individual reddening values, deriving unreddened parameters that are used for the main sequence fit. We identify 43 likely members of Pismis 11. We study the variation of extinction across the face of the cluster and find some dispersion, with a trend to higher values in the immediate neighbourhood of HD 80077. We estimate a distance of 3.6 kpc for the cluster. If HD 80077 is a member, it has M_bol<-10.5 and it is one of the three visually brightest stars in the Galaxy. Several early type stars in the vicinity of Pismis~11 fit well the cluster sequence and are likely to represent an extended population at the same distance. About 18 arcmin to the North of Pismis 11, we find a small concentration of stars, which form a clear sequence. We identify this group as a previously uncatalogued open cluster, which we provisionally call Alicante 5. The distance to Alicante 5 is also 3.6 kpc, suggesting that these two clusters and neighbouring early-type stars form a small association. Based on its proper motion, HD 80077 is not a runaway star and may be a member of the cluster. If this is the case, it would be one of the brightest stars in the Galaxy.Comment: 25 pages. It contains many figures and tables. Accepted for publication in Astronomy and Astrophysic

A new survey of cool supergiants in the Magellanic Clouds

In this study, we conduct a pilot program aimed at the red supergiant population of the Magellanic Clouds. We intend to extend the current known sample to the unexplored low end of the brightness distribution of these stars, building a more representative dataset with which to extrapolate their behaviour to other Galactic and extra-galactic environments. We select candidates using only near infrared photometry, and with medium resolution multi-object spectroscopy, we perform spectral classification and derive their line-of-sight velocities, confirming the nature of the candidates and their membership to the clouds. Around two hundred new RSGs have been detected, hinting at a yet to be observed large population. Using near and mid infrared photometry we study the brightness distribution of these stars, the onset of mass-loss and the effect of dust in their atmospheres. Based on this sample, new a priori classification criteria are investigated, combining mid and near infrared photometry to improve the observational efficiency of similar programs as this.Comment: 39 pages, 10 figures. Accepted for publication in A&

Una colección por descubrir: museo catedralicio de Valencia.

Treball Final de Grau en Turisme. Codi: TU0944. Curs: 2017/201

Sistemas de comunicación aumentativos y alternativos en la escuela ordinaria para alumnos con TEA

Treball Final de Grau en Mestre o Mestra d'Educació Primària. Codi: MP1040. Curs: 2014/2015La inclusión es uno de los objetivos de la escuela ordinaria. Además, la legislación vigente reconoce que son las Administración educativas las responsables de facilitar los recursos necesarios que garanticen la igualdad de oportunidades a los alumnos/as con Necesidades Educativas de Apoyo Educativo (NEAE) a través de la escuela. Por ello, con el presente trabajo se pretende dar a conocer una serie de materiales elaborados utilizando los Sistemas de Comunicación Aumentativos y Alternativos (SCAA), concretamente aquellos que requieren de apoyo externo, el trabajo mediante intercambio de pictogramas (PECS) y la creación de nuevos materiales, así como describir una metodología de intervención educativa que ha resultado de utilidad para facilitar el acceso al currículum de Educación Primaria de un alumno con Trastorno del Espectro Autista (TEA), utilizando su centro de interés para trabajar diferentes campos semánticos para la adquisición de nuevo vocabulari

The population of M-type supergiants in the starburst cluster Stephenson 2

The open cluster Stephenson 2 contains the largest collection of red supergiants known in the Galaxy, and at present is the second most massive young cluster known in the Milky Way. We have obtained multi-epoch, intermediate-resolution spectra around the CaII triplet for more than 30 red supergiants in Stephenson~2 and its surroundings. We find a clear separation between a majority of RSGs having spectral types M0-M2 and the brightest members in the NIR, which have very late spectral types and show strong evidence for heavy mass loss. The distribution of spectral types is similar to that of RSGs in other clusters, such as NGC 7419, or associations, like Per OB1. The cluster data strongly support the idea that heavy mass loss and maser emission is preferentially associated with late-M spectral types, suggesting that they represent an evolutionary phase.Comment: Contribution to the Betelgeuse workshop, November 2012, Paris. To be published in the European Astronomical Society Publications Series, editors: Pierre Kervella, Thibaut Le Bertre & Guy Perri

Social Exclusion and Convergence in the EU: An Assessment of the Europe 2020 Strategy

Economic convergence has long been a declared objective of the EU and considered the fundamental mechanism for achieving socioeconomic cohesion. The recent economic crisis had an uneven impact across EU countries and brought a halt to the process of economic and social convergence. In response to this situation, the Europe 2020 strategy, launched in 2010, aimed to deliver social and territorial cohesion in the Member States. In this paper we evaluate the poverty and social exclusion pillar of the Europe 2020 strategy by analysing whether it has promoted convergence across the EU countries in the indicators devised to capture risk of poverty, severe material deprivation, and the number of persons living in households with very low work intensity. Our results for all three rates indicate that convergence occurs in heterogeneous clubs that do not follow a geographic east‒west or south‒north pattern. Convergence within each club, especially for the severe deprivation rate, takes place by means of a catching-up process, with Eastern European levels converging on the Western levels. Finally, not only is there club convergence, but there is no tendency for the clubs to convergence. Poverty and social cohesion indicators show a multi-speed Europe, casting doubt on the sustainability of the overall convergence process in the EU

The upper sequence of young open clusters is shaped by binary interaction

The upper main-sequence of young star clusters displays a spread in colour that is very difficult to explain in terms of single star evolution. In recent years, it has been interpreted as a combination of the effects of rotation and mass transfer in multiple systems on the evolution of individual stars. I will present the results of a large spectroscopic survey of massive stars in open clusters in the 10-100 Ma age range, confirming that blue supergiants are in most cases far too massive for the corresponding cluster turn-off. We have used a large grid of FASTWIND models to derive stellar parameters, finding that a substantial fraction of blue supergiants in clusters have masses equivalent to two turn-off stars. Combined with the Gaia results on membership, these results suggest that most stars at the top of cluster sequences are the product of binary interaction. If the masses derived are to be believed, many blue supergiants are the results of mergers

Cluster membership for the long-period Cepheid calibrator SV Vul

Classical Cepheids represent the first step of the distance scale ladder. Claims of tension between the locally calculated Hubble constant and the values deduced from Planck’s results have sparked new interest in these distance calibrators. Cluster membership provides an independent distance measurement, as well as astrophysical context for studies of their stellar properties. Here, we report the discovery of a young open cluster in the vicinity of SV Vul, one of the most luminous Cepheids known in the Milky Way. Gaia DR2 data show that SV Vul is a clear astrometric and photometric member of the new cluster, which we name Alicante 13. Although dispersed, Alicante 13 is moderately well populated, and contains three other luminous stars, one early-A bright giant and two low-luminosity red supergiants. The cluster is about 30 Ma old at a nominal distance of 2.5 kpc. With this age, SV Vul should have a mass around 10 M⊙, in good accordance with its luminosity, close to the highest luminosity for Cepheids allowed by recent stellar models.This research is partially supported by the Spanish Ministerio de Ciencia e Innovación under grants AYA2015-68012-C2-2-P and PGC2018-093741-B-C21/C22 (MCI/AEI/FEDER, UE)