دورية أكاديمية

Extremely Red Galaxies at z = 5–9 with MIRI and NIRSpec: Dusty Galaxies or Obscured Active Galactic Nuclei?

التفاصيل البيبلوغرافية
العنوان: Extremely Red Galaxies at z = 5–9 with MIRI and NIRSpec: Dusty Galaxies or Obscured Active Galactic Nuclei?
المؤلفون: Guillermo Barro, Pablo G. Pérez-González, Dale D. Kocevski, Elizabeth J. McGrath, Jonathan R. Trump, Raymond C. Simons, Rachel S. Somerville, L. Y. Aaron Yung, Pablo Arrabal Haro, Hollis B. Akins, Michaela B. Bagley, Nikko J. Cleri, Luca Costantin, Kelcey Davis, Mark Dickinson, Steve L. Finkelstein, Mauro Giavalisco, Carlos Gómez-Guijarro, Nimish P. Hathi, Michaela Hirschmann, Benne W. Holwerda, Marc Huertas-Company, Jeyhan S. Kartaltepe, Anton M. Koekemoer, Ray A. Lucas, Casey Papovich, Nor Pirzkal, Lise-Marie Seillé, Sandro Tacchella, Stijn Wuyts, Stephen M. Wilkins, Alexander de la Vega, Guang Yang, Jorge A. Zavala
المصدر: The Astrophysical Journal, Vol 963, Iss 2, p 128 (2024)
بيانات النشر: IOP Publishing, 2024.
سنة النشر: 2024
المجموعة: LCC:Astrophysics
مصطلحات موضوعية: Galaxy formation, Galaxy evolution, High-redshift galaxies, Stellar populations, James Webb Space Telescope, Galaxy photometry, Astrophysics, QB460-466
الوصف: We study a new population of extremely red objects (EROs) recently discovered by the James Webb Space Telescope (JWST) based on their NIRCam colors F277W − F444W > 1.5 mag. We find 37 EROs in the Cosmic Evolution Early Release Science Survey (CEERS) field with F444W < 28 mag and photometric redshifts between 5 < z < 7, with median $z={6.9}_{-1.6}^{+1.0}$ . Surprisingly, despite their red long-wavelength colors, these EROs have blue short-wavelength colors (F150W − F200W ∼ 0 mag) indicative of bimodal spectral energy distributions (SEDs) with a red, steep slope in the rest-frame optical, and a blue, flat slope in the rest-frame UV. Moreover, all these EROs are unresolved, point-like sources in all NIRCam bands. We analyze the SEDs of eight of them with MIRI and NIRSpec observations using stellar population models and active galactic nucleus (AGN) templates. We find that dusty galaxies or obscured AGNs provide similarly good SED fits but different stellar properties: massive and dusty, $\mathrm{log}{M}_{\star }/{M}_{\odot }$ ∼ 10 and A _V ≳ 3 mag, or low mass and obscured, $\mathrm{log}{M}_{\star }/{M}_{\odot }$ ∼ 7.5 and A _V ∼ 0 mag, hosting an obscured quasi-stellar object (QSO). SED modeling does not favor either scenario, but their unresolved sizes are more suggestive of AGNs. If any EROs are confirmed to have $\mathrm{log}{M}_{\star }/{M}_{\odot }$ ≳ 10.5, it would increase the pre-JWST number density at z > 7 by up to a factor ∼60. Similarly, if they are QSOs with luminosities in the L _bol > 10 ^45–46 erg s ^−1 range, their number would exceed that of bright blue QSOs by more than three orders of magnitude. Additional photometry at mid-infrared wavelengths will reveal the true nature of the red continuum emission in these EROs and will place this puzzling population in the right context of galaxy evolution.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1538-4357
Relation: https://doaj.org/toc/1538-4357
DOI: 10.3847/1538-4357/ad167e
URL الوصول: https://doaj.org/article/9dcf87e376414a54aad66e12ebdb9330
رقم الأكسشن: edsdoj.9dcf87e376414a54aad66e12ebdb9330
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:15384357
DOI:10.3847/1538-4357/ad167e