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Search Results: 1 - 10 of 410 matches for " Carme Gallart "
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Observational discovery of the AGB-bump in densely populated color-magnitude diagrams of galaxies and star clusters
Carme Gallart
Physics , 1997, DOI: 10.1086/311218
Abstract: The huge photometric databases that are being created for stars in the Magellanic Clouds and in Local Group galaxies not only allow detailed study of the star formation history of these systems, but also provide important information on stellar evolutionary theory. Two low-level features above the red-clump in the LMC color-magnitude diagram (CMD) have been discussed by Zaritsky & Lin (1997) and Alcock et al. (1997) as the possible signature of an intervening population. I conclude that one of the features, which has also been associated with the red giant branch bump (RGB-bump) predicted by theory and observed in globular clusters, is instead produced during asymtotic giant branch (AGB) evolution. I will call it the AGB-bump. In this paper, it will be shown that the stellar evolution predictions about the position and strength of the AGB-bump are in very good agreement with the observed structures in the LMC, M31 and globular clusters. The position in the CMD of the other feature is consistent with the location of the blue-loops of a few Myr old stars and it has also been observed in the CMD of other galaxies with a young stellar population.
The star formation history of resolved galaxies: Composite H-R diagram
Carme Gallart
Physics , 2000,
Abstract: I discuss the information provided by color-magnitude diagrams of different absolute magnitude limits in the study of the star formation histories of nearby galaxies. I review the recent progress made in the field, with emphasis on the results for Local Group dwarf galaxies.
La riquesa de la burgesia de Barcelona: el cas d'Elisenda de banyeres (segle XIII)
Batlle i Gallart, Carme
Anuario de Estudios Medievales , 2002,
Abstract: This is another contribution to the history of the upper class of Barcelona’s society in the 13th century in particular the Banyeres lineage, now with the biography of the couple Joan and Elisenda. It analyses, specially, their testaments, the inventories of the house, urban properties, vineyards and so on with their incomes, and also the lawsuits for the inheritance's possession between the Church and Elisenda and after between benefical institutions to feeding the poors, who remained the only Banyeres heirs. Aquesta és una nova contribució a la historia de la classe dominant de la societat barcelonina en el segle XIII, concretament de la família Banyeres. Es tracta del matrimoni format per Elisenda de Sant Quirze i Joan de Banyeres. S'estudien els testaments, inventaris de la casa, propietats urbanes, vinyes, rendes, censos, com també els litigis sostinguts entre l'Església i Elisenda de Banyeres per la possessió de la herència i després entre les institucions benèfiques que donaven menjar ais pobres, que foren els hereus deis Banyeres.
Guillem Eimeric, a Jurist of a Patrician Family of Barcelona ( 1301)
Batlle i Gallart, Carme
Anuario de Estudios Medievales , 2007,
Abstract: The aim of this article is to draw the biography of Guillem Eimeric, a Jurist born in Barcelona, who lived in the second half of 13th century. The study is based on the Guillem Eimeric’s will and on the inventory of his properties and goods. Among his goods, his rich Library deserves to be especially mentionned. The paper finishes with a study of the lineage from Eimeric de Perusia and with an analysis of the banking affairs of his relatives. L’objecte d’aquest article és tra ar la biografia de Guillem Eimeric, jurista de Barcelona, que visqué a la segona meitat del segle XIII. El treball es basa sobretot en l’anàlisi del seu testament i en l’inventari dels seus béns, entre els quals destaca una rica biblioteca. L’article es completa amb l’estudi del llinatge procedent d’Eimeric de Perusia i dels negocis realitzats pels seus familiars banquers.
A Better Look at Learning: How Does the Brain Express the Mind?  [PDF]
Frederic Perez-Alvarez, Alexandra Perez-Serra, Carme Timoneda-Gallart
Psychology (PSYCH) , 2013, DOI: 10.4236/psych.2013.410108
Abstract:

Learning problems in the light of PASS assessment and intervention were studied. Data for 248 subjects with specific learning impairment (SLI), dyslexia, dyscalculia, and non-defined learning difficulty were studied. Hierarchical cluster analysis of PASS scores at baseline was performed. PASS re-assessment was carried out at 6 and 12 months after 6-month period of intervention. Four statistically different cluster groups were identified. All groups, except one, showed cognitive weakness. Planning weakness, associated with other weakness, appears involved in all groups except two where isolated planning and successive weaknesses were identified, respectively. SLI, dyslexia, and dyscalculia are not homogenous entities. A kind of dyslexia is clearly linked to isolated successive weakness. SLI-expressive (SLIe) and a minority of both dyslexia and dyscalculia appear linked to successive weakness although associated with planning and additionally with attention in the case of SLIe. SLI-expressive-receptive (SLIe-r) and Dyscalculia appear linked to simultaneous weakness, although associated with planning weakness. Other kind of SLIe-r appears linked to isolated planning weakness. Other types of SLIe-r and Dyscalculia appear liked to combined planning + successive + attention weakness. Isolated dysfunctional attention does not appear in any case. After 6 months of intervention, planning improves statistically in all cases. Attention improves in few cases. Successive and simultaneous do not improve. The best result is in dyslexia, SLIe and a minority of Dyscalculia. The worst result is in those without cognitive deficiency. The effect of intervention at 6 months remains with minor changes at 12 months after 6 months without intervention.

The stellar structures around disk galaxies
Igor Drozdovsky,Antonio Aparicio,Carme Gallart,Matteo Monelli
Revista mexicana de astronomía y astrofísica , 2007,
Abstract: We present a brief summary of current results on the stellar distribution and population gra- dients in disk galaxies, and discuss future prospects of follow-up imaging and spectro- scopic research using the GTC with OSIRIS & EMIR.
The Star Formation History of the Local Group dwarf galaxy Leo I
Carme Gallart,Wendy Freedman,Antonio Aparicio,Gianpaolo Bertelli,Cesare Chiosi
Physics , 1999, DOI: 10.1086/301078
Abstract: We present a quantitative analysis of the star formation history (SFH) of the Local Group dSph galaxy Leo I, from the information in its HST [(V-I),I] color-magnitude diagram (CMD). The method we use is based in comparing, via synthetic CMDs, the expected distribution of stars in the CMD for different evolutionary scenarios, with the observed distribution. We consider the SFH to be composed by the SFR(t), the Z(t), the IMF, and a function $\beta(f,q)$, controlling the fraction $f$ and mass ratio distribution $q$ of binary stars. The comparison between the observed CMD and the model CMDs is done through chi-square minimization of the differences in the number of stars in a set of regions of the CMD. Our solution for the SFH of Leo I defines a minimum of chi-square in a well defined position of the parameter space, and the derived SFR(t) is robust, in the sense that its main characteristics are unchanged for different combinations of the remaining parameters. However, only a narrow range of assumptions for Z(t), IMF and $\beta(f,q)$ result in a good agreement between the data and the models, namely: Z=0.0004, a Kroupa et al. (1993) IMF or slightly steeper, and a relatively large fraction of binary stars. Most star formation activity (70% to 80%) occurred between 7 and 1 Gyr ago. At 1 Gyr ago, it abruptly dropped to a negligible value, but seems to have been active until at least ~ 300 Myr ago. Our results don't unambiguously answer the question of whether Leo I began forming stars around 15 Gyr ago, but it appears that the amount of this star formation, if existing at all, would be small.
Proper motions of Local Group dwarf spheroidal galaxies I: First ground-based results for Fornax
René. A. Méndez,Edgardo Costa,Mario H. Pedreros,Maximiliano Moyano,Martin Altmann,Carme Gallart
Physics , 2010, DOI: 10.1086/655149
Abstract: In this paper we present in detail the methodology and the first results of a ground-based program to determine the absolute proper motion of the Fornax dwarf spheroidal galaxy. The proper motion was determined using bona-fide Fornax star members measured with respect to a fiducial at-rest background spectroscopically confirmed Quasar, \qso. Our homogeneous measurements, based on this one Quasar gives a value of (\mua,\mud)$ = (0.64 \pm 0.08, -0.01 \pm 0.11)$ \masy. There are only two other (astrometric) determinations for the transverse motion of Fornax: one based on a combination of plates and HST data, and another (of higher internal precision) based on HST data. We show that our proper motion errors are similar to those derived from HST measurements on individual QSOs. We provide evidence that, as far as we can determine it, our motion is not affected by magnitude, color, or other potential systematic effects. Last epoch measurements and reductions are underway for other four Quasar fields of this galaxy, which, when combined, should yield proper motions with a weighted mean error of $\sim50\,\mu$as y$^{-1}$, allowing us to place important constraints on the orbit of Fornax.
First ground-based CCD proper motions for Fornax II: Final results
Rene. A. Mendez,Edgardo Costa,Carme Gallart,Mario H. Pedreros,Maximiliano Moyano,Martin Altmann
Physics , 2011, DOI: 10.1088/0004-6256/142/3/93
Abstract: We present the first entirely ground-based astrometric determination of the proper motion for the Fornax Local Group Dwarf Spheroidal satellite galaxy of the Milky Way, using CCD data acquired with the ESO 3.5 m NTT telescope at La Silla Observatory in Chile. Our unweighted mean from five Quasar fields in the background of Fornax, used as fiducial reference points, leads to $\mu_\alpha \cos \delta=0.62 \pm 0.16$ $\masy$, and $\mu_\delta=-0.53 \pm 0.15$ $\masy$. A detailed comparison with all previous measurements of this quantity seems to imply that there is still no convincing convergence to a single value, perhaps indicating the existence of unnacounted systematic effects in (some of) these measurements. From all available proper motion and radial velocity measurements for Fornax, we compute Fornax's orbital parameters and their uncertainty using a realistic Galactic potential and a Monte Carlo simulation. Properties of the derived orbits are then compared to main star formation episodes in the history of Fornax. All published proper motion values imply that Fornax has recently (200-300 Myr ago) approached perigalacticon at a distance of $\sim$150 kpc. However, the derived period exhibits a large scatter, as does the apogalacticon. Our orbit, being the most energetic, implies a very large apogalactic distance of $\sim 950$ kpc. If this were the case, then Fornax would be a representative of an hypervelocity MW satellite in late infall.
Old Main Sequence Turnoff Photometry in the Small Magellanic Cloud. II. Star Formation History and Its Spatial Gradients
Noelia E. D. Noel,Antonio Aparicio,Carme Gallart,Sebastian L. Hidalgo,Edgardo Costa,Rene A. Mendez
Physics , 2009, DOI: 10.1088/0004-637X/705/2/1260
Abstract: We present a quantitative analysis of the SFH of 12 fields in the SMC. We find that there are four main periods of enhancement of star formation: a young one peaked at around 0.2-0.5 Gyr old, only present in the eastern and in the central-most fields; two at intermediate ages present in all fields (a conspicuous one peaked at 4-5 Gyr old, and a less significant one peaked at 1.5-2.5); and an old one, peaked at 10 Gyr in all fields but the western ones. In the western fields, this old enhancement splits into two, one peaked at around 8 Gyr old and another at around 12 Gyr old. This "two-enhancement" zone seems to be a robust feature since it is unaffected by our choice of stellar evolutionary library but more data covering other fields of the SMC are necessary in order to ascertain its significancy. Some correlation could exist with encounters taken from the orbit determination of Kallivayalil et al. (2006). But our results would be also fit in a first pericenter passage scenario like the one claimed by Besla et al. (2007). There is a strong dichotomy between East/Southeast and West in the current irregular shape of the SMC. We find that this dichotomy is produced by the youngest population and began about 1 Gyr ago or later. We do not find yet a region dominated by an old halo at 4.5 kpc from the SMC center, indicating either that this old stellar halo does not exist in the SMC or that its contribution to the stellar populations, at the galactocentric distances of our outermost field, is negligible. We derive the age-metallicity relation and find that the metallicity increased continuously from early epochs until now.
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