What Are Those Tiny Things? A First Study of Compact Star Clusters in the SMACS0723 Field with JWST
| Autor: | Andreas Faisst, Ranga Ram Chary, Gabriel Brammer, Sune Toft |
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| Rok vydání: | 2022 |
| Předmět: |
ILLUSTRIS PROJECT
DWARF GALAXIES FORMATION EFFICIENCIES FOS: Physical sciences ASSEMBLY HISTORY Astronomy and Astrophysics EVOLUTIONARY SYNTHESIS MASS Astrophysics - Astrophysics of Galaxies COSMOS FIELD STELLAR POPULATION SYNTHESIS SYSTEMS Space and Planetary Science GLOBULAR-CLUSTERS Astrophysics of Galaxies (astro-ph.GA) |
| Zdroj: | Faisst, A L L, Chary, R R, Brammer, G & Toft, S 2022, ' What Are Those Tiny Things? A First Study of Compact Star Clusters in the SMACS0723 Field with JWST ', Astrophysical Journal Letters, vol. 941, no. 1, L11 . https://doi.org/10.3847/2041-8213/aca1bf |
| DOI: | 10.48550/arxiv.2208.05502 |
| Popis: | We use the unprecedented resolution and depth of the JWST NIRCam Early Release Observations at 1-5 $\mu$m to study the stellar mass, age, and metallicity of compact star clusters in the neighborhood of the host galaxies in the SMACS J0723.3-7327 galaxy cluster field at z = 0.39. The measured colors of these star clusters show a similar distribution as quiescent galaxies at the same redshift, but are >3 magnitudes fainter than the current depths of wide-field galaxy survey. The star clusters are unresolved in the NIRCam/F150W data suggesting sizes smaller than 50pc. This is significantly smaller than star forming clumps or dwarf galaxies in local galaxies. From fitting their photometry with simple stellar population (SSP) models, we find stellar metallicities consistent with 0.2-0.3 $Z_{\odot}$ and ages of $1.5^{+0.5}_{-0.5}$ Gyrs. We rule out metallicities Comment: 20 pages, 8 figures, 2 tables. Accepted for publication in ApJ |
| Databáze: | OpenAIRE |
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