TY - JOUR

T1 - Early Results from GLASS-JWST. XV. Properties of the Faintest Red Sources in the NIRCAM Deep Fields

AU - Glazebrook, K.

AU - Nanayakkara, T.

AU - Jacobs, C.

AU - Leethochawalit, N.

AU - Calabrò, A.

AU - Bonchi, A.

AU - Castellano, M.

AU - Fontana, A.

AU - Mason, C.

AU - Merlin, E.

AU - Morishita, T.

AU - Paris, D.

AU - Trenti, M.

AU - Treu, T.

AU - Santini, P.

AU - Wang, X.

AU - Boyett, K.

AU - Bradac, Marusa

AU - Brammer, G.

AU - Jones, T.

AU - Marchesini, D.

AU - Nonino, M.

AU - Vulcani, B.

N1 - Funding Information: This work is based on observations made with the NASA/ESA/CSA James Webb Space Telescope. The data were obtained from the Mikulski Archive for Space Telescopes at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127 for JWST. These observations are associated with program JWST-ERS-1324. The specific JWST observations analyzed in this article can be accessed via doi: 10.17909/mrt6-wm89 . We acknowledge financial support from NASA through grants JWST-ERS-1342. Funding Information: This work is based on observations made with the NASA/ESA/CSA James Webb Space Telescope. The data were obtained from the Mikulski Archive for Space Telescopes at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127 for JWST. These observations are associated with program JWST-ERS-1324. The specific JWST observations analyzed in this article can be accessed via doi:10.17909/mrt6-wm89. We acknowledge financial support from NASA through grants JWST-ERS-1342. Funding Information: K.G., T.N., and C.J. acknowledge support from Australian Research Council Laureate Fellowship FL180100060. N.L. and M.T. acknowledge support by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. C.M. acknowledges support by the VILLUM FONDEN under grant 37459. The Cosmic Dawn Center (DAWN) is funded by the Danish National Research Foundation under grant DNRF140. M.B. acknowledges support from the Slovenian national research agency ARRS through grant N1-0238. Publisher Copyright: © 2023. The Author(s). Published by the American Astronomical Society.

PY - 2023

Y1 - 2023

N2 - We present a first look at the reddest 2-5 μm sources found in deep images from the GLASS Early Release Science program. We undertake a general search, i.e., not looking for any particular spectral signatures, for sources detected only in bands redder than is reachable with the Hubble Space Telescope, and which would likely not have been identified in pre-JWST surveys. We search for sources down to AB ∼27 (corresponding to >10σ detection threshold) in any of the F200W to F444W filters, with a >1 magnitude excess relative to F090W to F150W bands. Fainter than F444W >25 we find 56 such sources of which 37 have reasonably constrained spectral energy distributions to which we can fit photometric redshifts. We find the majority of this population (∼65%) as 2 < z < 6 star-forming low-attenuation galaxies that are faint at rest-frame ultraviolet-optical wavelengths, have stellar masses 108.5-109.5 M ⊙, and have observed fluxes at >2 μm boosted by a combination of the Balmer break and emission lines. The typical implied rest equivalent widths are ∼200 Å with some extreme objects up to ∼1000 Å. This is in contrast with brighter magnitudes where the red sources tend to be z < 3 quiescent galaxies and dusty star-forming objects. Our general selection criteria for red sources allow us to independently identify other phenomena as diverse as extremely low-mass (∼108 M ⊙) quiescent galaxies at z < 1, recovering recently identified z > 11 galaxies and a very cool brown dwarf.

AB - We present a first look at the reddest 2-5 μm sources found in deep images from the GLASS Early Release Science program. We undertake a general search, i.e., not looking for any particular spectral signatures, for sources detected only in bands redder than is reachable with the Hubble Space Telescope, and which would likely not have been identified in pre-JWST surveys. We search for sources down to AB ∼27 (corresponding to >10σ detection threshold) in any of the F200W to F444W filters, with a >1 magnitude excess relative to F090W to F150W bands. Fainter than F444W >25 we find 56 such sources of which 37 have reasonably constrained spectral energy distributions to which we can fit photometric redshifts. We find the majority of this population (∼65%) as 2 < z < 6 star-forming low-attenuation galaxies that are faint at rest-frame ultraviolet-optical wavelengths, have stellar masses 108.5-109.5 M ⊙, and have observed fluxes at >2 μm boosted by a combination of the Balmer break and emission lines. The typical implied rest equivalent widths are ∼200 Å with some extreme objects up to ∼1000 Å. This is in contrast with brighter magnitudes where the red sources tend to be z < 3 quiescent galaxies and dusty star-forming objects. Our general selection criteria for red sources allow us to independently identify other phenomena as diverse as extremely low-mass (∼108 M ⊙) quiescent galaxies at z < 1, recovering recently identified z > 11 galaxies and a very cool brown dwarf.

U2 - 10.3847/2041-8213/acba8b

DO - 10.3847/2041-8213/acba8b

M3 - Journal article

AN - SCOPUS:85153796442

VL - 947

JO - The Astrophysical Journal Letters

JF - The Astrophysical Journal Letters

SN - 2041-8205

IS - 2

M1 - L25

ER -