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标题：High angular resolution study of the super star cluster population in IRAS 17138−1017 ⋆
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作者：N. T. Lam ; D. Gratadour ; D. Rouan 等
期刊名称：Astronomy & Astrophysics
印刷版ISSN：0004-6361
电子版ISSN：1432-0746
出版年度：2020
卷号：639
页码：1-10
DOI：10.1051/0004-6361/202037755
语种：English
出版社：EDP Sciences
摘要：Aims.Currently, the global characteristics and evolution of super star clusters (SSCs) are not well understood, due to the large distances to their host galaxies. We aim to study the population of SSCs in IRAS 17138-1017, a luminous infrared galaxy (LIRG), in terms of age, extinction, mass, and luminosity distribution.Methods.We analyzed imaging data in the near-infrared from the GeMS/GSAOI instrument on the Gemini telescope and generated simulations with the radiative transfer code MontAGN. The extraction of SSCs from the images and their photometry inJ,H, andKsallowed us to derive color-color and color-magnitude diagrams. Comparison with a theoretical stellar evolutionary track gives a first hint into the extinction towards each SSC, as well as their ages, despite some degeneracy between those two quantities. Spectra given by our radiative transfer code MontAGN, which includes dust emission, also provide insightful predictions and comparisons.Results.We detect with a fair degree of confidence 54 SSCs ofmKsbetween 16 mag and 21 mag with a median instrumental uncertainty of 0.05 mag. When plotted on a color–color diagram and a color–magnitude diagram, it appears that most of the sources are very much extinct with respect to an intrinsic theoretical evolutionary track. Once de-reddened, the colors point unambiguously to two distinct and very recent starburst episodes at 2.8 and 4.5 Myr. While the SSCs in the 4.5 Myr starburst are distributed along the spiral arms, the 2.8 Myr SSCs are concentrated in the central region. The luminosity and mass functions present a classical power-law behavior, although with shallower slopes than generally observed in LIRGs. Comparison with radiative transfer simulations shows that, the dust thermal emission and scattered light are negligible and could not explain the few very red SSCs that could not be de-reddened safely.
关键词：engalaxies: individual: IRAS 17138-1017galaxies: starburstgalaxies: star clusters: generalradiative transferinfrared: galaxiesinstrumentation: high angular resolution