Abstract:
We present CCD photometry in the Washington system C and T 1 passbands down to T 1 ∼ 22 in the fields of L35, L45, L49, L50, L62, L63 and L85, seven poorly studied star clusters in the inner region of the Small Magellanic Cloud (SMC). We measured T 1 magnitudes and C - T 1 colours for a total of 114 826 stars distributed throughout cluster areas of 13.7 × 13.7 arcmin 2 each. Cluster radii were estimated from star counts distributed throughout the entire observed fields. The seven clusters are generally characterized by a relatively small angular size and by a high field star contamination. We performed an in-depth analysis of the field star contamination of the colour-magnitude diagrams (CMDs), and statistically cleaned the cluster CMDs. Based on the best fits of isochrones computed by the Padova group to the (T 1, C - T 1) CMDs, we derive ages for the sample, assuming Z = 0.004, finding ages between 25 Myr and 1.2 Gyr. We then examined different relationships between positions in the SMC, age and metallicity of a larger sample of clusters including our previous work whose ages and metallicities are on the same scale used in this paper. We confirm previous results in the sense that the further a cluster is from the centre of the galaxy, the older and more metal poor it is, with some dispersion; although clusters associated with the Magellanic Bridge clearly do not obey the general trend. The number of clusters within ∼ 2°of the SMC centre appears to have increased substantially after ∼2.5 Gyr ago, hinting at a burst. © 2008 RAS.
Registro:
Documento: |
Artículo
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Título: | Seven young star clusters in the inner region of the Small Magellanic Cloud |
Autor: | Piatti, A.E.; Geisler, D.; Sarajedini, A.; Gallart, C.; Wischnjewsky, M. |
Filiación: | Instituto de Astronomía y Física del Espacio, CC 67, Suc. 28, 1428 Ciudad de Buenos Aires, Argentina Grupo de Astronomía, Departamento de Física, Universidad de Concepción, Casilla 160-C, Concepción, Chile Department of Astronomy, University of Florida, PO Box 112055, Gainesville, FL 32611, United States Instituto de Astrofísica de Canarias, Calle Vía Laćtea, E-38200 La Laguna, Tenerife, Spain Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile
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Palabras clave: | Galaxies: individual: SMC; Galaxies: star clusters; Magellanic Clouds; Techniques: photometric |
Año: | 2008
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Volumen: | 389
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Número: | 1
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Página de inicio: | 429
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Página de fin: | 440
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DOI: |
http://dx.doi.org/10.1111/j.1365-2966.2008.13593.x |
Título revista: | Monthly Notices of the Royal Astronomical Society
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Título revista abreviado: | Mon. Not. R. Astron. Soc.
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ISSN: | 00358711
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CODEN: | MNRAA
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Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00358711_v389_n1_p429_Piatti |
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Citas:
---------- APA ----------
Piatti, A.E., Geisler, D., Sarajedini, A., Gallart, C. & Wischnjewsky, M.
(2008)
. Seven young star clusters in the inner region of the Small Magellanic Cloud. Monthly Notices of the Royal Astronomical Society, 389(1), 429-440.
http://dx.doi.org/10.1111/j.1365-2966.2008.13593.x---------- CHICAGO ----------
Piatti, A.E., Geisler, D., Sarajedini, A., Gallart, C., Wischnjewsky, M.
"Seven young star clusters in the inner region of the Small Magellanic Cloud"
. Monthly Notices of the Royal Astronomical Society 389, no. 1
(2008) : 429-440.
http://dx.doi.org/10.1111/j.1365-2966.2008.13593.x---------- MLA ----------
Piatti, A.E., Geisler, D., Sarajedini, A., Gallart, C., Wischnjewsky, M.
"Seven young star clusters in the inner region of the Small Magellanic Cloud"
. Monthly Notices of the Royal Astronomical Society, vol. 389, no. 1, 2008, pp. 429-440.
http://dx.doi.org/10.1111/j.1365-2966.2008.13593.x---------- VANCOUVER ----------
Piatti, A.E., Geisler, D., Sarajedini, A., Gallart, C., Wischnjewsky, M. Seven young star clusters in the inner region of the Small Magellanic Cloud. Mon. Not. R. Astron. Soc. 2008;389(1):429-440.
http://dx.doi.org/10.1111/j.1365-2966.2008.13593.x