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Dating star clusters in the Small Magellanic Cloud by means of integrated spectra
In this study flux-calibrated integrated spectra in the range(3600-6800) Å are presented for 16 concentrated star clusters inthe Small Magellanic Cloud (SMC), approximately half of which constituteunstudied objects. We have estimated ages and foreground interstellarreddening values from the comparison of the line strengths and continuumdistribution of the cluster spectra with those of template clusterspectra with known parameters. Most of the sample clusters are youngblue clusters (6-50 Myr), while L 28, NGC 643 and L 114 are found to beintermediate-age clusters (1-6 Gyr). One well known SMC cluster (NGC416) was observed for comparison purposes. The sample includes clustersin the surroundings and main body of the SMC, and the derived foregroundreddening values are in the range 0.00 <= E(B-V) <= 0.15. Thepresent data also make up a cluster spectral library at SMC metallicity.Based on observations made at Complejo Astronómico El Leoncito,which is operated under agreement between the Consejo Nacional deInvestigaciones Científicas y Técnicas de laRepública Argentina and the National Universities of La Plata,Córdoba and San Juan, Argentina.
| Magellanic Clouds stellar clusters. II. New B,V CM diagrams for 6 LMC and 10 SMC clusters
We present new CCD photometry for 6 LMC and 10 SMC stellar clusterstaken at the ESO 1.54-m Danish Telescope in La Silla, to extend aprevious investigation on Magellanic Clouds clusters based on HSTsnapshots. Thanks to the much larger area covered by the Danishdetector, we investigate the spatial distribution of cluster stars,giving V, (B-V) CM diagrams for both clusters and surrounding fields.Evidence of a complex history of star formation in the Clouds isoutlined, showing that old field populations in both Clouds havemetallicities much lower than normally adopted for them (Z = 0.008 and Z= 0.004 for LMC and SMC respectively), with SMC field stars more metalpoor than in the LMC. Observational data concerning the red clump offield stars in both Clouds are briefly discussed. Based on observationscarried out at the European Southern Observatory, La Silla, Chile.
| Exploring Star Cluster Properties at the SMC Metallicity Level
Not Available
| Dust and CO emission in normal spirals. I. The data.
We present 1300μm continuum observations and measurements of the CO(1-0) and (2-1) emission from the inner regions of 98 normal galaxies.The spatial resolution ranges from 11" to 45". The sources come from acomplete FIR selected sample of 138 inactive spirals with an opticaldiameter D_25_<=180".
| A Revised and Extended Catalog of Magellanic System Clusters, Associations, and Emission Nebulae. I. Small Magellanic Cloud and Bridge
A survey of extended objects in the Magellanic System was carried out onthe ESO/SERC R and J Sky Survey Atlases. The present work is dedicatedto the Small Magellanic Cloud and to the inter-Magellanic Cloud region("Bridge") totaling 1188 objects, of which 554 are classified as starclusters, 343 are emissionless associations, and 291 are related toemission nebulae. The survey includes cross-identifications amongcatalogs, and we present 284 new objects. We provide accurate positions,classification, homogeneous sizes, and position angles, as well asinformation on cluster pairs and hierarchical relation for superimposedobjects. Two clumps of extended objects in the Bridge and one at theSmall Magellanic Cloud wing tip might be currently forming dwarfspheroidal galaxies.
| Accurate positions for SMC clusters
Positions of 203 SMC clusters accurate to + or - 5 arcsec are reported.The astrometry method used is briefly described. Plans for futureMagellanic Cloud cluster astrometry are summarized.
| Observed radii and structural parameters of star clusters in the SMC. III
The tidal radii, concentration parameters, and masses of 24 starclusters in the SMC have been derived by means of star counts. In thisinvestigation the seven most distant clusters (with projected distancesfrom the rotation center similar to the halo radius) are included aswell, and their masses are found to be about one hundred times lowerthan those of the halo clusters of the Galaxy.
| Ages and metallicities of LMC and SMC red clusters through H-beta and G band photometry
Narrow band integrated photometry of the H-beta and G band absorptionfeatures for 41 LMC and 10 SMC red star clusters is presented. Anage-metallicity calibration is provided for the color-color diagram. SWBtypes between IV and VII are derived for 23 unclassified clusters, andtheir distribution in the age versus metallicity plane is discussed. Astudy of chemical evolution of the Magellanic Clouds has shown that theLMC presents a steeper chemical enrichment slope. An intrinsicmetallicity dispersion is found in the LMC chemical evolution,indicating that the gas has been inhomogeneous at any time, with localenrichment prevailing over a global one. One zone model describes theevolution of both clouds, the efficiency of star cluster formation beinglarger in the LMC. The LMC presents a burst of star cluster formation att = 4.5 x 10 to the 9th yr. New B - V data for fainter SMC clusters arealso presented, providing an essentially complete color histogram forclusters with globular cluster appearance.
| Magnitudes of Clusters in the Small Magellanic Cloud
Not Available
| The cluster system of the Small Magellanic Cloud
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958MNRAS.118..172L&db_key=AST
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