Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Structural parameters of seven small magellanic cloud intermediate-age and old star clusters
AU - Glatt, Katharina
AU - Grebel, Eva K.
AU - Gallagher III, John S.
AU - Nota, Antonella
AU - Sabbi, Elena
AU - Sirianni, Marco
AU - Clementini, Gisella
AU - Costa, Gary Da
AU - Tosi, Monica
AU - Harbeck, Daniel
AU - Koch, Andreas
AU - Kayser, Andrea
N1 - 16 pages, 13 figures
PY - 2009/10/1
Y1 - 2009/10/1
N2 - We present structural parameters for the seven intermediate-age and old star clusters NGC 121, Lindsay 1, Kron 3, NGC 339, NGC 416, Lindsay 38, and NGC 419 in the Small Magellanic Cloud (SMC). We fit King profiles and Elson, Fall, and Freeman profiles to both surface-brightness and star-count data taken with the Advanced Camera for Surveys aboard the Hubble Space Telescope. Clusters older than ~1 Gyr show a spread in cluster core radii that increases with age, while the youngest clusters have relatively compact cores. No evidence for post-core-collapse clusters was found. We find no correlation between core radius and distance from the SMC center, although consistent with other studies of dwarf galaxies, some relatively old and massive clusters have low densities. The oldest SMC star cluster, the only globular NGC121, is the most elliptical object of the studied clusters. No correlation is seen between ellipticity and distance from the SMC center. The structures of these massive intermediate-age (1-8 Gyr) SMC star clusters thus appear to primarily result from internal evolutionary processes.
AB - We present structural parameters for the seven intermediate-age and old star clusters NGC 121, Lindsay 1, Kron 3, NGC 339, NGC 416, Lindsay 38, and NGC 419 in the Small Magellanic Cloud (SMC). We fit King profiles and Elson, Fall, and Freeman profiles to both surface-brightness and star-count data taken with the Advanced Camera for Surveys aboard the Hubble Space Telescope. Clusters older than ~1 Gyr show a spread in cluster core radii that increases with age, while the youngest clusters have relatively compact cores. No evidence for post-core-collapse clusters was found. We find no correlation between core radius and distance from the SMC center, although consistent with other studies of dwarf galaxies, some relatively old and massive clusters have low densities. The oldest SMC star cluster, the only globular NGC121, is the most elliptical object of the studied clusters. No correlation is seen between ellipticity and distance from the SMC center. The structures of these massive intermediate-age (1-8 Gyr) SMC star clusters thus appear to primarily result from internal evolutionary processes.
KW - astro-ph.CO
KW - astro-ph.GA
U2 - 10.1088/0004-6256/138/5/1403
DO - 10.1088/0004-6256/138/5/1403
M3 - Journal article
VL - 138
SP - 1403
EP - 1416
JO - The Astronomical Journal
JF - The Astronomical Journal
SN - 0004-6256
IS - 5
ER -