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Arxiv: Polycyclic aromatic hydrocarbon (PAH) luminous galaxies in JWST CEERS data Published: 1/2/2024 7:35:14 AM Updated: 1/2/2024 7:35:14 AM

Paper abstract: It has been an unanswered question how many dusty galaxies have beenundetected from the state-of-the-art observational surveys. JWST enables us todetect faint IR galaxies that have prominent polycyclic aromatic hydrocarbon(PAH) features in the mid-IR wavelengths. PAH is a valuable tracer of starformation and dust properties in the mid-infrared wavelength. The JWST CosmicEvolution Early Release Science (CEERS) fields provide us with wavelengthcoverage from 7.7 to 21 \mum using six photometric bands of the mid-infraredinstrument (MIRI). We have identified galaxies dominated by mid-IR emissionfrom PAHs, termed PAH galaxies. From our multi-band photometry catalogue, weselected ten PAH galaxies displaying high flux ratios of \log(S_{15}/S_{10}) >0.8. The SED fitting analysis indicates that these galaxies are star-forminggalaxies with total IR luminosities of 10^{10} ~ 10^{11.5} L_{\odot}at z ~ 1. The morphology of PAH galaxies does not show any clearsignatures of major merging or interaction within the MIRI resolution. Themajority of them are on the star-formation main sequence at z ~ 1. Ourresult demonstrates that JWST can detect PAH emissions from normal star-forminggalaxies at z ~ 1, in addition to ultra-luminous infrared galaxies(ULIRGs) or luminous infrared galaxies (LIRGs).