We present a search for extremely red, dust-obscured, z > 7 galaxies with JWST/NIRCam+MIRI imaging over the first 20 arcmin(2) of publicly available Cycle 1 data from the COSMOS-Web, CEERS, and PRIMER surveys. Based on their red color in F277W-F444W (similar to 2.5 mag) and detection in MIRI/F770W (similar to 25 mag), we identify two galaxies, COS-z8M1 and CEERS-z7M1, that have best-fit photometric redshifts of z = 8.4(-0.4)(+0.3) and 7.6(-0.1)(+0.1), respectively. We perform spectral energy distribution fitting with a variety of codes (including BAGPIPES, PROSPECTOR, BEAGLE, and CIGALE) and find a >95% probability that these indeed lie at z > 7. Both sources are compact (R-eff less than or similar to 200 pc) and highly obscured (A(V) similar to 1.5-2.5) and, at our best-fit redshift estimates, likely have strong [O III]+H beta emission contributing to their 4.4 mu m photometry. We estimate stellar masses of similar to 10(10) M-circle dot for both sources; by virtue of detection in MIRI at 7.7 mu m, these measurements are robust to the inclusion of bright emission lines, for example, from an active galactic nucleus. We identify a marginal (2.9 sigma) Atacama Large Millimeter/submillimeter Array detection at 2 mm within 0 ''.5 of COS-z8M1, which, if real, would suggest a remarkably high IR luminosity of similar to 10(12) L-circle dot. These two galaxies, if confirmed at z similar to 8, would be extreme in their stellar and dust masses and may be representative of a substantial population of highly dust-obscured galaxies at cosmic dawn.
Two Massive, Compact, and Dust-obscured Candidate z ≃ 8 Galaxies Discovered by JWST / Akins, Hollis B.; Casey, Caitlin M.; Allen, Natalie; Bagley, Micaela B.; Dickinson, Mark; Finkelstein, Steven L.; Franco, Maximilien; Harish, Santosh; Arrabal Haro, Pablo; Ilbert, Olivier; Kartaltepe, Jeyhan S.; Koekemoer, Anton M.; Liu, Daizhong; Long, Arianna S.; McCracken, Henry Joy; Paquereau, Louise; Papovich, Casey; Pirzkal, Nor; Rhodes, Jason; Robertson, Brant E.; Shuntov, Marko; Toft, Sune; Yang, Guang; Barro, Guillermo; Bisigello, Laura; Buat, Véronique; Champagne, Jaclyn B.; Cooper, Olivia; Costantin, Luca; de la Vega, Alexander; Drakos, Nicole E.; Faisst, Andreas; Fontana, Adriano; Fujimoto, Seiji; Gillman, Steven; Gómez-Guijarro, Carlos; Gozaliasl, Ghassem; Hathi, Nimish P.; Hayward, Christopher C.; Hirschmann, Michaela; Holwerda, Benne W.; Jin, Shuowen; Kocevski, Dale D.; Kokorev, Vasily; Lambrides, Erini; Lucas, Ray A.; Magdis, Georgios E.; Magnelli, Benjamin; McKinney, Jed; Mobasher, Bahram; Pérez-González, Pablo G.; Rich, R. Michael; Seillé, Lise-Marie; Talia, Margherita; Urry, C. Megan; Valentino, Francesco; Whitaker, Katherine E.; Yung, L. Y. Aaron; Zavala, Jorge; null, null. - In: THE ASTROPHYSICAL JOURNAL. - ISSN 0004-637X. - STAMPA. - 956:1(2023), pp. 61.61-61.61. [10.3847/1538-4357/acef21]
Two Massive, Compact, and Dust-obscured Candidate z ≃ 8 Galaxies Discovered by JWST
Talia, MargheritaMembro del Collaboration Group
;
2023
Abstract
We present a search for extremely red, dust-obscured, z > 7 galaxies with JWST/NIRCam+MIRI imaging over the first 20 arcmin(2) of publicly available Cycle 1 data from the COSMOS-Web, CEERS, and PRIMER surveys. Based on their red color in F277W-F444W (similar to 2.5 mag) and detection in MIRI/F770W (similar to 25 mag), we identify two galaxies, COS-z8M1 and CEERS-z7M1, that have best-fit photometric redshifts of z = 8.4(-0.4)(+0.3) and 7.6(-0.1)(+0.1), respectively. We perform spectral energy distribution fitting with a variety of codes (including BAGPIPES, PROSPECTOR, BEAGLE, and CIGALE) and find a >95% probability that these indeed lie at z > 7. Both sources are compact (R-eff less than or similar to 200 pc) and highly obscured (A(V) similar to 1.5-2.5) and, at our best-fit redshift estimates, likely have strong [O III]+H beta emission contributing to their 4.4 mu m photometry. We estimate stellar masses of similar to 10(10) M-circle dot for both sources; by virtue of detection in MIRI at 7.7 mu m, these measurements are robust to the inclusion of bright emission lines, for example, from an active galactic nucleus. We identify a marginal (2.9 sigma) Atacama Large Millimeter/submillimeter Array detection at 2 mm within 0 ''.5 of COS-z8M1, which, if real, would suggest a remarkably high IR luminosity of similar to 10(12) L-circle dot. These two galaxies, if confirmed at z similar to 8, would be extreme in their stellar and dust masses and may be representative of a substantial population of highly dust-obscured galaxies at cosmic dawn.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
